diff --git a/apps/presentation/dashboard/src/features/personal-workspace/goal-research-history.tsx b/apps/presentation/dashboard/src/features/personal-workspace/goal-research-history.tsx
index 0c5851f8ab..0b5a88953f 100644
--- a/apps/presentation/dashboard/src/features/personal-workspace/goal-research-history.tsx
+++ b/apps/presentation/dashboard/src/features/personal-workspace/goal-research-history.tsx
@@ -5,19 +5,19 @@ import {Fragment, useEffect, useId, useLayoutEffect, useMemo, useRef, useState}
 import {defaultParseSearch} from "@tanstack/react-router";
 import {ResearchRecordSearch} from "./research-record-browser";
 import {ResearchAnalysisButton, ResearchAnalysisPanel, ResearchAnalysisStatus, ResearchCitationPanel, ResearchProgressSummary, ResearchReportSummary, ResearchCaseReading, useResearchAnalysis} from "./goal-research-analysis";
-import {buildExploreTimeline, parseExploreFindingSections, type TimelineFinding} from "../../../../../../loopx/control_plane/presentation/explore_timeline.js";
+import {buildExploreTimeline, latestExploreFindingInPhase, parseExploreFindingSections, type TimelineFinding} from "../../../../../../loopx/control_plane/presentation/explore_timeline.js";
 import {GoalResearchTimeline} from "./goal-research-timeline";
 import {requestJson} from "../../data/chat";
 import {sourceReadApiUrl} from "../../data/local-status-query";
 import {ContextHelp} from "./context-help";
 import type {WorkspaceGoal} from "./personal-workspace-model";
-import {groupUnlinkedHistoryQuestions, layoutExploreHistory, mergeExploreHistoryEvents, parseExploreHistoryPage, projectExploreHistory, type ExploreHistoryEvent} from "../../../../../../loopx/control_plane/presentation/explore_history.js";
+import {groupUnlinkedHistoryQuestions, layoutExploreHistory, mergeExploreHistoryEvents, parseExploreHistoryPage, projectExploreHistory, type ExploreHistoryEvent, type ExploreHistoryNode} from "../../../../../../loopx/control_plane/presentation/explore_history.js";
 import "./goal-research-history.css";
 import {ExploreMeasurements, formatExploreMeasurementValue} from "./explore-measurements";
 import {projectTrajectoryDisplay, trajectoryDisplaySnapshotText} from "../../../../../../loopx/control_plane/capabilities/trajectory_assessment_display.js";
 
 type CollectionSelection = {nodes: string[]; day: string | null};
-type Selection = CollectionSelection & {finding?: string; collection?: CollectionSelection; question?: boolean; returnKey?: string};
+type Selection = CollectionSelection & {finding?: string; event?: string; collection?: CollectionSelection; question?: boolean; returnKey?: string};
 type Lens = "timeline" | "graph";
 type Read = {events: ExploreHistoryEvent[]; total: number | null; complete: boolean};
 const selectedFromUrl = (goal: string): Selection => {
@@ -37,7 +37,7 @@ const selectedFromUrl = (goal: string): Selection => {
   const collection = nodes.length === 1 && (parentDay !== null || (parentNodes.length > 1 && parentNodes.includes(nodes[0]!)))
     ? {nodes: parentDay === null ? parentNodes : [], day: parentDay} : undefined;
   const finding = query.get("research_finding") || undefined;
-  return {nodes, day, finding, collection, question: query.get("research_question") === "1" || !finding,
+  return {nodes, day, finding, event: query.get("research_event") || undefined, collection, question: query.get("research_question") === "1" || !finding,
     returnKey: query.get("research_return") || undefined};
 };
 
@@ -285,8 +285,14 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
   const positions = new Map(layout.map(item => [item.node.id, item]));
   const selectedId = selection.nodes.length === 1 ? selection.nodes[0]! : "";
   const selected = value?.nodes.find(node => node.id === selectedId);
-  const selectedFinding = selected?.findings.find(finding => finding.result_id === selection.finding)
-    ?? (!selection.finding ? selected?.findings.at(-1) : undefined);
+  const findingVersions = value?.events.filter(event => event.event_kind === "finding" && event.node_id === selectedId) ?? [];
+  const defaultFinding = (node: ExploreHistoryNode) => (
+    lens === "timeline" && phase !== null && timeline ? latestExploreFindingInPhase(timeline, node.id, phase) : undefined
+  ) ?? node.findings.at(-1);
+  const selectedFinding = selected && (selection.event
+    ? findingVersions.find(finding => finding.event_id === selection.event && (!selection.finding || finding.result_id === selection.finding))
+    : selection.finding ? selected.findings.find(finding => finding.result_id === selection.finding)
+    : defaultFinding(selected));
   const hasSeparateQuestion = Boolean(selected?.findings.length && selectedFinding?.title !== selected.latest.title);
   const selectedGroup = selection.day !== null ? grouped.groups.find(group => group.day === selection.day) : undefined;
   const selectedMembers = selectedGroup?.nodes ?? (selection.nodes.length > 1 ? value?.nodes.filter(node => selection.nodes.includes(node.id)) : undefined);
@@ -353,12 +359,14 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
     setSelection(next);
     const url = new URL(window.location.href);
     url.searchParams.delete("research_node"); url.searchParams.delete("research_group"); url.searchParams.delete("research_finding");
+    url.searchParams.delete("research_event");
     url.searchParams.delete("research_parent_node"); url.searchParams.delete("research_parent_group");
     url.searchParams.delete("research_question"); url.searchParams.delete("research_return");
     if (next.nodes.length || next.day !== null) {
       if (next.day !== null) url.searchParams.set("research_group", next.day);
       else url.searchParams.set("research_node", next.nodes.length === 1 ? next.nodes[0]! : JSON.stringify(next.nodes));
       if (next.finding) url.searchParams.set("research_finding", next.finding);
+      if (next.event) url.searchParams.set("research_event", next.event);
       if (next.question) url.searchParams.set("research_question", "1");
       if (next.returnKey) url.searchParams.set("research_return", next.returnKey);
       if (next.collection?.day !== null && next.collection?.day !== undefined) url.searchParams.set("research_parent_group", next.collection.day);
@@ -366,9 +374,9 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
       url.searchParams.set("research_goal", goalId);
     }
     else url.searchParams.set("research_goal", goalId);
-    if (selection.finding !== next.finding || selection.question !== next.question || selection.returnKey !== next.returnKey || selection.day !== next.day || selection.nodes.length !== next.nodes.length || selection.nodes.some((id, index) => id !== next.nodes[index])) window.history.pushState(null, "", url);
+    if (selection.finding !== next.finding || selection.event !== next.event || selection.question !== next.question || selection.returnKey !== next.returnKey || selection.day !== next.day || selection.nodes.length !== next.nodes.length || selection.nodes.some((id, index) => id !== next.nodes[index])) window.history.pushState(null, "", url);
   };
-  const choose = (id: string, focus = true, finding?: string, returnKey?: string) => {collectionOpener.current = null; select({nodes: id ? [id] : [], day: null, finding, returnKey}, focus);};
+  const choose = (id: string, focus = true, finding?: string, returnKey?: string, event?: string) => {collectionOpener.current = null; select({nodes: id ? [id] : [], day: null, finding, event, returnKey}, focus);};
   const closeReader = () => {
     focusPending.current = false;
     focusReturn.current = {nodeId: collection ? selectedId : undefined, eventId: selectedFinding?.event_id,
@@ -377,8 +385,9 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
     collectionOpener.current = null;
     select(collection ?? {nodes: [], day: null}, false);
   };
-  const chooseQuestion = (node: NonNullable<typeof value>["nodes"][number], parent: CollectionSelection) => {
-    select({nodes: [node.id], day: null, finding: node.findings.at(-1)?.result_id, collection: parent});
+  const chooseQuestion = (node: ExploreHistoryNode, parent: CollectionSelection) => {
+    const finding = defaultFinding(node);
+    select({nodes: [node.id], day: null, finding: finding?.result_id, event: finding?.event_id, collection: parent});
   };
   const resultsAnchor = useRef<HTMLDivElement>(null), reportAnchor = useRef<HTMLDivElement>(null), historyAnchor = useRef<HTMLElement>(null);
   const reportEntries = useRef(new Set<string>());
@@ -409,14 +418,16 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
   // Pin the first displayed finding to its stable identity. New source records
   // must not move a reader, and reload/Back must restore that same evidence.
   useEffect(() => {
-    if (!active || selection.finding || !selectedFinding || !selected) return;
+    if (!active || selection.event || !selectedFinding || !selected) return;
     const finding = selectedFinding.result_id;
-    setSelection(previous => ({...previous, finding}));
+    const event = selectedFinding.event_id;
+    setSelection(previous => ({...previous, finding, event}));
     const url = new URL(window.location.href);
     url.searchParams.set("research_finding", finding);
+    url.searchParams.set("research_event", event);
     if (questionExpanded) url.searchParams.set("research_question", "1");
     window.history.replaceState(null, "", url);
-  }, [active, selection.finding, selectedFinding, selected, questionExpanded]);
+  }, [active, selection.event, selectedFinding, selected, questionExpanded]);
   const displayControl = display ? <div className="research-display-language">
       <button type="button" disabled={!currentDisplay} aria-pressed={originalDisplay} onClick={() => setOriginalDisplay(value => !value)}>
         {originalDisplay ? (zh ? "查看译文" : "Show translation") : (zh ? "查看原文" : "Show originals")}
@@ -433,7 +444,7 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
   const historyView = !value ? null : lens === "timeline" && timeline ? <div className="research-history-canvas is-timeline" ref={graph} tabIndex={-1}>
         <GoalResearchTimeline timeline={timeline} zh={zh} selectedIds={selection.nodes} selectedEventId={selectedFinding?.event_id} selectedDay={selection.day} dayGroups={grouped.groups}
           onGroupSelect={(day, button) => select({nodes: [], day}, true, button)} phase={phase} onPhase={next => chooseView(lens, next)}
-          onSelect={(id, finding) => choose(id, true, finding)} onSelectMany={(nodes, button) => select({nodes, day: null}, true, button)} timeLabel={fullTime} dayLabel={dayTime}/>
+          onSelect={(id, finding, event) => choose(id, true, finding, undefined, event)} onSelectMany={(nodes, button) => select({nodes, day: null}, true, button)} timeLabel={fullTime} dayLabel={dayTime}/>
       </div> : <div className="research-history-canvas" ref={graph} tabIndex={0} aria-label={zh ? "完整已载入研究关系图；可滚动" : "Full loaded research graph; scrollable"}>
         <div className="research-history-stage" style={{width, height}}>
           <svg width={width} height={height} aria-hidden="true" className="research-history-edges">
@@ -608,21 +619,22 @@ export function GoalResearchHistory({goalId, originalGoalId = goalId, preferHist
         </details> : null : <h3>{selected.latest.title}</h3> : null}{displayControl}
         {selected.latest.blocked_reason ? <p className="research-history-error">{selected.latest.blocked_reason}</p> : null}
         {selected.findings.length ? <>
-          {selected.findings.length > 1 ? <nav className="research-finding-navigation" aria-label={zh ? "问题结论" : "Question findings"}>
-            <label><span>{zh ? "结论" : "Finding"}</span><select aria-label={zh ? "选择问题结论" : "Choose a question finding"} value={selectedFinding?.result_id ?? ""}
-                onChange={event => select({...selection, finding: event.target.value, question: false}, false)}>
+          {findingVersions.length > 1 ? <nav className="research-finding-navigation" aria-label={zh ? "问题结论" : "Question findings"}>
+            <label><span>{zh ? "结论" : "Finding"}</span><select aria-label={zh ? "选择问题结论" : "Choose a question finding"} value={selectedFinding?.event_id ?? ""}
+                onChange={event => {const finding = findingVersions.find(finding => finding.event_id === event.target.value);
+                  if (finding) select({...selection, finding: finding.result_id, event: finding.event_id, question: false}, false);}}>
                 {!selectedFinding ? <option value="" disabled>{zh ? "所选结论未找到" : "Selected finding not found"}</option> : null}
-                {selected.findings.map((finding, index) => <option key={finding.result_id} value={finding.result_id}>
+                {findingVersions.map((finding, index) => <option key={finding.event_id} value={finding.event_id}>
                   {index + 1}. {finding.title} · {stateLabel(finding.status)} · {timeLabel(finding.recorded_at)}
                 </option>)}
               </select>
             </label>
             <div className="research-finding-steps">
-              <span>{selectedFinding ? selected.findings.indexOf(selectedFinding) + 1 : "—"} / {selected.findings.length}</span>
+              <span>{selectedFinding ? findingVersions.indexOf(selectedFinding) + 1 : "—"} / {findingVersions.length}</span>
               {([-1, 1] as const).map(step => {
-                const next = selectedFinding ? selected.findings[selected.findings.indexOf(selectedFinding) + step] : undefined;
+                const next = selectedFinding ? findingVersions[findingVersions.indexOf(selectedFinding) + step] : undefined;
                 return <button key={step} type="button" disabled={!next} aria-label={step < 0 ? (zh ? "上一条结论" : "Previous finding") : (zh ? "下一条结论" : "Next finding")}
-                  onClick={() => {if (next) select({...selection, finding: next.result_id, question: false}, false);}}>
+                  onClick={() => {if (next) select({...selection, finding: next.result_id, event: next.event_id, question: false}, false);}}>
                   {step < 0 ? <ArrowLeft size={16} aria-hidden/> : <ArrowRight size={16} aria-hidden/>}
                 </button>;
               })}
diff --git a/apps/presentation/dashboard/src/features/personal-workspace/goal-research-timeline.tsx b/apps/presentation/dashboard/src/features/personal-workspace/goal-research-timeline.tsx
index c0c2290e7b..610115a35e 100644
--- a/apps/presentation/dashboard/src/features/personal-workspace/goal-research-timeline.tsx
+++ b/apps/presentation/dashboard/src/features/personal-workspace/goal-research-timeline.tsx
@@ -13,7 +13,7 @@ type Copy = Record<string, string>;
 type Props = {
   timeline: ExploreTimeline; zh: boolean; selectedIds: readonly string[]; selectedEventId?: string; phase: number | null;
   selectedDay: string | null; dayGroups: ReturnType<typeof groupUnlinkedHistoryQuestions>["groups"]; onGroupSelect: (day: string, button: HTMLButtonElement) => void;
-  onSelect: (id: string, finding?: string) => void; onSelectMany: (ids: string[], button: HTMLButtonElement) => void; onPhase: (index: number | null) => void;
+  onSelect: (id: string, finding?: string, event?: string) => void; onSelectMany: (ids: string[], button: HTMLButtonElement) => void; onPhase: (index: number | null) => void;
   timeLabel: (value: number, precise?: boolean) => string; dayLabel: (value: number) => string;
 };
 
@@ -51,7 +51,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
   }, [timeline.start, timeline.end]);
   const findingCopy = exploreFindingCopy(zh);
   const copy: Copy = zh ? {
-    early: "前段", middle: "中段", late: "后段", item: "研究项", items: "研究项", question: "个问题", questions: "个问题",
+    early: "前段", middle: "中段", late: "后段", item: "个有记录的研究项", items: "个有记录的研究项", question: "个问题", questions: "个问题",
     decisions: "显式决策", none: "未记录显式决策", changed: "变化", stopped: "停止", retained: "保留",
     unstructured: "决策未结构化", unstructuredHint: "结论未按 writeback 结构记录，无法拆出依据与决策。",
     density: "记录密度", densityHint: "柱高为事件数；浅红为无记录空档", axis: "自首条记录起",
@@ -62,7 +62,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
     noTime: "没有可用的记录时间，无法放上时间轴；下方记录仍可完整阅读。",
     whole: "全程",
   } : {
-    early: "Early", middle: "Middle", late: "Late", item: "Research item", items: "Research items", question: "question", questions: "questions",
+    early: "Early", middle: "Middle", late: "Late", item: "research item with records", items: "research items with records", question: "question", questions: "questions",
     decisions: "Explicit decisions", none: "No explicit decision recorded", changed: "Changed", stopped: "Stopped", retained: "Retained",
     unstructured: "Unstructured decisions", unstructuredHint: "Findings were not recorded in writeback sections; evidence and decisions cannot be separated.",
     density: "Recording density", densityHint: "Bar height is events; pale red is a recording gap", axis: "Since first record",
@@ -79,6 +79,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
   const span = Math.max(1, elapsed);
   const pct = (at: number) => `${((at - start) / span) * 100}%`;
   const inPhase = (at: number | null) => phase === null || exploreTimelinePhaseAt(timeline.phases, at) === phase;
+  const nodeInPhase = (item: TimelineNode) => phase === null || item.recordedPhases.has(phase);
   const label = (key: string) => copy[key] ?? key;
   const hours = (from: number, to: number) => { const value = (to - from) / 3_600_000; return value >= 48 ? `${(value / 24).toFixed(1)} ${zh ? "天" : "d"}` : `${value.toFixed(1)} ${zh ? "小时" : "h"}`; };
   const maxEvents = Math.max(1, ...timeline.bins.map(bin => bin.events));
@@ -87,7 +88,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
   const marker = (item: TimelineNode, style: CSSProperties, extra = "") => {
     const title = `${item.node.latest.title} · ${label(item.label || "unlabeled")}${item.first !== null ? ` · ${timeLabel(item.first)}` : ""}`;
     return <button key={item.node.id} type="button" title={title} aria-label={title} aria-pressed={selectedIds.includes(item.node.id)} data-research-nodes={item.node.id}
-      className={`research-timeline-marker ${tone(item.label)}${isOpen(item) ? " is-open" : ""}${selectedIds.includes(item.node.id) ? " is-selected" : ""}${inPhase(item.first) ? "" : " is-dimmed"}${extra}`}
+      className={`research-timeline-marker ${tone(item.label)}${isOpen(item) ? " is-open" : ""}${selectedIds.includes(item.node.id) ? " is-selected" : ""}${nodeInPhase(item) ? "" : " is-dimmed"}${extra}`}
       style={style} onClick={() => onSelect(item.node.id)}/>;
   };
   const points = (items: readonly TimelineNode[], extra = "") => groupExploreTimelinePoints(items, start, end, plotWidth).map(group => {
@@ -97,7 +98,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
     const title = zh ? `${ids.length} 项相邻研究 · ${timeLabel(group.items[0]!.first!)} — ${timeLabel(group.items.at(-1)!.first!)} · 展开全部记录与依据`
       : `${ids.length} nearby research items · ${timeLabel(group.items[0]!.first!)} — ${timeLabel(group.items.at(-1)!.first!)} · Read every record and source`;
     return <button key={ids[0]} type="button" title={title} aria-label={title} aria-pressed={selected} data-research-nodes={ids.join(" ")}
-      className={`research-timeline-marker is-cluster${selected ? " is-selected" : ""}${group.items.some(item => inPhase(item.first)) ? "" : " is-dimmed"}`}
+      className={`research-timeline-marker is-cluster${selected ? " is-selected" : ""}${group.items.some(nodeInPhase) ? "" : " is-dimmed"}`}
       style={{left: pct(group.at)}} onClick={event => onSelectMany(ids, event.currentTarget)}><span>{ids.length}</span></button>;
   });
   const trail = groupExploreTimelineDecisions(timeline, phase);
@@ -139,6 +140,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
       <p>{findingCopy.meaning}</p>
       {!timeline.structuredCount ? <p>{copy.unstructuredHint}</p> : null}
       <p>{copy.routeHint}{zh ? "。" : ". "}{zh ? "相邻点合拢，数字为研究项数，一次展开原始时间与依据。" : "Nearby points group; the number counts research items. Select once for original times and sources."}</p>
+      <p>{zh ? "选中时段后，高亮其中有记录的研究项。各项位置仍按首次记录时间。" : "Selecting a period highlights items with records in it. Each item stays at its first recorded time."}</p>
       <p>{zh ? "未关联问题按首次记录 UTC 日期收纳，不推断路线或因果。决策轨迹按研究问题归组，组内保留各轮显式决策，最近记录在前；同名问题不会自动合并。" : "Unlinked questions group by first-record UTC date, without inferring a route or cause. Decision history groups explicit decisions by question, newest record first; matching titles do not merge questions."}</p>
       <dl className="research-phase-details">{timeline.phases.map(item => <div key={item.index}><dt>{phaseName(item)}</dt><dd>{phaseDescription(item)}</dd></div>)}</dl>
         </ContextHelp>{phase !== null ? <button type="button" className="research-link" onClick={() => onPhase(null)}>{copy.all}</button> : null}
@@ -206,7 +208,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
       {dayGroups.length ? <>
         <div className="research-row-label"><strong>{copy.singles} · {groupedIds.size}</strong></div>
         <div className="research-unlinked-days">{dayGroups.map(group => <button type="button" key={group.day} data-research-day={group.day} aria-pressed={selectedDay === group.day}
-          className={`${selectedDay === group.day ? "is-selected" : ""}${group.nodes.some(node => inPhase(timeline.nodes.get(node.id)!.first)) ? "" : " is-dimmed"}`}
+          className={`${selectedDay === group.day ? "is-selected" : ""}${group.nodes.some(node => nodeInPhase(timeline.nodes.get(node.id)!)) ? "" : " is-dimmed"}`}
           onClick={event => onGroupSelect(group.day, event.currentTarget)}><time>{group.day ? `${group.day} UTC` : (zh ? "时间未知" : "Unknown time")}</time><strong>{group.nodes.length} {group.nodes.length === 1 ? copy.question : copy.questions}</strong></button>)}</div>
       </> : null}
       {swarm.length ? <>
@@ -231,7 +233,7 @@ export function GoalResearchTimeline({timeline, zh, selectedIds, selectedEventId
 
 function TrailList({groups, copy, label, timeLabel, selectedEventId, onSelect}: {
   groups: ReturnType<typeof groupExploreTimelineDecisions>; copy: Copy; label: (key: string) => string;
-  timeLabel: (value: number) => string; selectedEventId?: string; onSelect: (id: string, finding?: string) => void;
+  timeLabel: (value: number) => string; selectedEventId?: string; onSelect: Props["onSelect"];
 }) {
   const [limit, setLimit] = useState(3);
   const selectedIndex = groups.findIndex(group => group.items.some(item => item.event.event_id === selectedEventId));
@@ -248,7 +250,7 @@ function TrailList({groups, copy, label, timeLabel, selectedEventId, onSelect}:
 
 function TrailQuestion({group, copy, label, timeLabel, selectedEventId, onSelect}: {
   group: ReturnType<typeof groupExploreTimelineDecisions>[number]; copy: Copy; label: (key: string) => string;
-  timeLabel: (value: number) => string; selectedEventId?: string; onSelect: (id: string, finding?: string) => void;
+  timeLabel: (value: number) => string; selectedEventId?: string; onSelect: Props["onSelect"];
 }) {
   const [limit, setLimit] = useState(3);
   const selectedIndex = group.items.findIndex(item => item.event.event_id === selectedEventId);
@@ -275,7 +277,7 @@ function TrailQuestion({group, copy, label, timeLabel, selectedEventId, onSelect
         <button type="button" data-research-decision={item.event.event_id}
           aria-label={`${label(decision.outcome)} · ${item.at === null ? copy.unknownTime : timeLabel(item.at)} · ${label(item.event.status)} · ${item.event.title}`}
           className={selectedEventId === item.event.event_id ? "is-selected" : ""}
-          onClick={event => {event.currentTarget.focus({preventScroll: true}); onSelect(item.event.node_id, item.event.result_id);}}>
+          onClick={event => {event.currentTarget.focus({preventScroll: true}); onSelect(item.event.node_id, item.event.result_id, item.event.event_id);}}>
           <span className="research-trail-main">
             <span className="research-trail-meta"><b className={`research-outcome is-${decision.outcome}`}>{label(decision.outcome)}</b>
               <time dateTime={item.at === null ? undefined : item.event.recorded_at}>{item.at === null ? copy.unknownTime : timeLabel(item.at)}</time>
diff --git a/apps/presentation/dashboard/src/router.tsx b/apps/presentation/dashboard/src/router.tsx
index 5b25981ab1..7d62c83df0 100644
--- a/apps/presentation/dashboard/src/router.tsx
+++ b/apps/presentation/dashboard/src/router.tsx
@@ -36,6 +36,7 @@ const searchSchema = z.object({
   research_goal: z.unknown().optional(),
   research_node: z.unknown().optional(),
   research_finding: z.unknown().optional(),
+  research_event: z.unknown().optional(),
   research_group: z.unknown().optional(),
   research_pack: z.unknown().optional(),
   research_analysis: z.unknown().optional(),
diff --git a/apps/presentation/dashboard/src/views/dashboard-page.tsx b/apps/presentation/dashboard/src/views/dashboard-page.tsx
index 842a61de6c..232cf5785e 100644
--- a/apps/presentation/dashboard/src/views/dashboard-page.tsx
+++ b/apps/presentation/dashboard/src/views/dashboard-page.tsx
@@ -3639,7 +3639,7 @@ export function DashboardPage() {
             workSession: sameStatusSource ? current.workSession : undefined,
             // Node/pack ids are source-local even when the Goal ids coincide.
             // Back restores the original source's URL and its own selection.
-            ...(runtimeSourceChanged ? {research_lens: undefined, research_phase: undefined, research_goal: undefined, research_node: undefined, research_finding: undefined,
+            ...(runtimeSourceChanged ? {research_lens: undefined, research_phase: undefined, research_goal: undefined, research_node: undefined, research_finding: undefined, research_event: undefined,
               research_group: undefined, research_analysis: undefined,
               research_analysis_goal: undefined, research_pack: undefined} : {}),
           };
diff --git a/docs/development/design.md b/docs/development/design.md
index 6d50d68d3c..5ff9dc5818 100644
--- a/docs/development/design.md
+++ b/docs/development/design.md
@@ -205,7 +205,9 @@ finding's full content. Do not invent short titles or infer findings from prose.
 A selected question is a focused document, not another full history stacked below
 the chart. Show one finding at a time with its declared status and full text;
 keep all findings selectable and failed or tentative counts visible. Preserve
-the exact finding on reload and Back. Offer the whole recorded history in place
+the exact finding event on reload and Back, including an earlier judgment later
+revised under the same finding identity. Period selection opens the original
+event from that period; current-state projection does not replace its text. Offer the whole recorded history in place
 and through the existing return action, without letting it bury the chosen text.
 When opening a specific finding, put its parent question in accessible contextual
 help rather than another collapsed title row. Opening a route's question still
@@ -221,6 +223,9 @@ with their outcome, change and recorded status; retain stopped/retained evidence
 and expose earlier records in place. Counts and date spans describe the selected
 time range. Keep negative and tentative record counts visible when older rows
 are folded, and open each row's exact finding in the existing reader.
+When opening a question from a selected timeline period, prefer its last
+readable finding recorded in that period. An explicitly chosen finding, the
+other findings and revisions in source history stay readable.
 
 In the loaded-record list, a node and its unambiguously linked finding share an
 entry after a complete read. Show the finding status beside the node's lifecycle
diff --git a/examples/personal-workspace-browser/research-finding-reader.mjs b/examples/personal-workspace-browser/research-finding-reader.mjs
index 9ab0439246..e3aadfb283 100644
--- a/examples/personal-workspace-browser/research-finding-reader.mjs
+++ b/examples/personal-workspace-browser/research-finding-reader.mjs
@@ -1,6 +1,6 @@
 import assert from "node:assert/strict";
 import {execFileSync} from "node:child_process";
-import {mkdtemp, rm} from "node:fs/promises";
+import {mkdtemp, readFile, rm} from "node:fs/promises";
 import {tmpdir} from "node:os";
 import {resolve} from "node:path";
 import {resolveTestPython} from "../../scripts/test-python.mjs";
@@ -52,6 +52,8 @@ export const researchFindingReaderScenario = {
     try {
       const fixture = resolve(temporary, "capture.json");
       writeFindingReaderFixture(fixture);
+      const capture = JSON.parse(await readFile(fixture, "utf8"));
+      const eventId = id => capture.events.find(event => event.event_kind === "finding" && event.result_id === id).event_id;
       owner = await startHistoryOwner(fixture);
       page = await browser.newPage({viewport: {width: 1440, height: 900}, hasTouch: true});
       if (collectCoverage) await page.coverage.startJSCoverage({resetOnNavigation: false});
@@ -65,7 +67,7 @@ export const researchFindingReaderScenario = {
       assert.equal(await page.getByText("开启研究模式", {exact: true}).count(), 0, "The read-only capture does not expose a configuration action");
       assert.equal(await picker.locator("option").count(), 20, "Every finding remains directly selectable");
       assert.equal(await article.count(), 1, "A dense question presents one full document, not twenty stacked documents");
-      assert.equal(await picker.inputValue(), "finding-19");
+      assert.equal(await picker.inputValue(), eventId("finding-19"));
       await page.waitForURL(/research_finding=finding-19/);
       assert.match(await reader.locator(".research-finding-exceptions").innerText(), /已反驳 3.*暂定结论 4/);
       assert.equal(await history.locator(".research-history-canvas").isVisible(), false, "The selected text leads; history is available on demand");
@@ -89,19 +91,19 @@ export const researchFindingReaderScenario = {
       await yardstick.locator(":scope > summary").click();
       await page.setViewportSize({width: 1440, height: 900});
 
-      await picker.selectOption("finding-0");
+      await picker.selectOption(eventId("finding-0"));
       assert.match(await article.innerText(), /已反驳/);
       assert.match(await article.innerText(), /观测 1：质量下降而延迟改善/);
       const completeObservation = await article.locator(".research-finding-sections dd").first().innerText();
       assert.equal(completeObservation.split("保留失败候选").length - 1, 3, "Selected long prose is complete");
       await page.reload({waitUntil: "domcontentloaded"});
       await picker.waitFor();
-      assert.equal(await picker.inputValue(), "finding-0", "Reload keeps the exact finding, not the latest one");
+      assert.equal(await picker.inputValue(), eventId("finding-0"), "Reload keeps the exact finding, not the latest one");
       await reader.getByRole("button", {name: "下一条结论", exact: true}).click();
-      assert.equal(await picker.inputValue(), "finding-1");
+      assert.equal(await picker.inputValue(), eventId("finding-1"));
       await page.goBack();
       await page.waitForFunction(() => new URL(location.href).searchParams.get("research_finding") === "finding-0");
-      assert.equal(await picker.inputValue(), "finding-0", "Back restores the prior finding");
+      assert.equal(await picker.inputValue(), eventId("finding-0"), "Back restores the prior finding");
 
       for (const width of [1440, 390]) {
         await page.setViewportSize({width, height: 900});
@@ -119,11 +121,11 @@ export const researchFindingReaderScenario = {
       }
       await reader.getByRole("button", {name: "下一条结论", exact: true}).focus();
       await page.keyboard.press("Enter");
-      assert.equal(await picker.inputValue(), "finding-1", "The complete collection works by keyboard");
+      assert.equal(await picker.inputValue(), eventId("finding-1"), "The complete collection works by keyboard");
       await reader.getByRole("button", {name: "上一条结论", exact: true}).tap();
-      assert.equal(await picker.inputValue(), "finding-0");
+      assert.equal(await picker.inputValue(), eventId("finding-0"));
       await reader.getByRole("button", {name: "下一条结论", exact: true}).tap();
-      assert.equal(await picker.inputValue(), "finding-1", "Narrow touch navigation keeps the selected record identity");
+      assert.equal(await picker.inputValue(), eventId("finding-1"), "Narrow touch navigation keeps the selected record identity");
       await page.screenshot({path: resolve(outputDir, "research-finding-reader-phone.png"), animations: "disabled"});
       await history.locator(".research-history-context > summary").click();
       assert.equal(await history.locator(".research-history-canvas").isVisible(), true);
@@ -150,7 +152,7 @@ export const researchFindingReaderScenario = {
         await older.focus();
         await page.keyboard.press("Enter");
         await picker.waitFor();
-        assert.equal(await picker.inputValue(), "finding-18", "An older decision opens its own finding, not the question's latest one");
+        assert.equal(await picker.inputValue(), eventId("finding-18"), "An older decision opens its own finding, not the question's latest one");
         assert.match(await article.innerText(), /观测 19：/);
         const heading = await article.getByRole("heading").boundingBox();
         const viewport = await page.locator(".personal-channel-scroll").boundingBox();
@@ -159,7 +161,7 @@ export const researchFindingReaderScenario = {
         await page.screenshot({path: resolve(outputDir, `research-decision-reader-${width}.png`), animations: "disabled"});
         await page.reload({waitUntil: "domcontentloaded"});
         await picker.waitFor();
-        assert.equal(await picker.inputValue(), "finding-18", "Reload retains the decision's exact finding");
+        assert.equal(await picker.inputValue(), eventId("finding-18"), "Reload retains the decision's exact finding");
         await reader.press("Escape");
 
         await group.getByRole("button", {name: /显示更早记录/}).click();
@@ -170,7 +172,7 @@ export const researchFindingReaderScenario = {
         await page.screenshot({path: resolve(outputDir, `research-decision-expanded-${width}.png`), animations: "disabled"});
         await earlier.tap();
         await picker.waitFor();
-        assert.equal(await picker.inputValue(), "finding-12");
+        assert.equal(await picker.inputValue(), eventId("finding-12"));
         assert.match(await article.innerText(), /观测 13：/);
         await reader.press("Escape");
         await reader.waitFor({state: "detached"});
@@ -178,7 +180,7 @@ export const researchFindingReaderScenario = {
         assert(await earlier.evaluate(element => element === document.activeElement), "Escape returns keyboard focus to the exact decision");
         await page.goBack();
         await picker.waitFor();
-        assert.equal(await picker.inputValue(), "finding-12", "Back restores the chosen historical decision");
+        assert.equal(await picker.inputValue(), eventId("finding-12"), "Back restores the chosen historical decision");
         await reader.press("Escape");
       }
 
@@ -202,7 +204,7 @@ export const researchFindingReaderScenario = {
       await picker.waitFor();
       assert.equal(await article.count(), 0, "An unknown explicit finding does not silently open a different record");
       assert.match(await reader.innerText(), /找不到所选结论/);
-      await picker.selectOption("finding-4");
+      await picker.selectOption(eventId("finding-4"));
       assert.match(await article.innerText(), /暂定结论/);
       await page.evaluate(() => localStorage.setItem("loopx-pw-locale", "en"));
       await page.reload({waitUntil: "domcontentloaded"});
diff --git a/examples/personal-workspace-browser/research-history.mjs b/examples/personal-workspace-browser/research-history.mjs
index 2d364d0f08..6eb99eaf65 100644
--- a/examples/personal-workspace-browser/research-history.mjs
+++ b/examples/personal-workspace-browser/research-history.mjs
@@ -181,6 +181,92 @@ for elapsed in (1900, 0, 9, 61002):
   }
 }
 
+// An original event is the reading identity even when the finding id is reused.
+export async function readRevisedFinding(browser) {
+  const directory = await mkdtemp(resolve(tmpdir(), "loopx-revised-finding-"));
+  const fixture = resolve(directory, "history.json"), goal = "synthetic-revised-finding";
+  const event = (kind, id, at, fields = {}) => ({schema_version: "loopx_explore_result_event_v0",
+    goal_id: goal, event_kind: kind, event_id: id, result_id: id, title: id,
+    recorded_at: `2026-01-01T${at}:00Z`, ...fields});
+  const finding = (id, at, fields) => event("finding", id, at, {node_id: "question", status: "tentative", ...fields});
+  const events = [event("node", "question", "00:00", {node_kind: "question", status: "open", title: "Same finding, successive judgments"}),
+    event("node", "neighbor", "01:30", {node_kind: "question", status: "open"}),
+    event("node", "last", "18:00", {node_kind: "question", status: "open"}),
+    finding("early-event", "03:00", {}),
+    finding("middle-event", "09:00", {result_id: "shared-finding", title: "Middle tentative judgment", summary: "MIDDLE-ORIGINAL: evidence is still uncertain."}),
+    finding("late-event", "18:00", {result_id: "shared-finding", title: "Late confirmed judgment", status: "confirmed", summary: "LATE-CONFIRMED: later evidence changes the conclusion."}),
+    finding("neighbor-middle", "08:00", {node_id: "neighbor"}), finding("neighbor-late", "17:00", {node_id: "neighbor", status: "confirmed"}),
+    finding("last-finding", "18:00", {node_id: "last", status: "confirmed"})];
+  await writeFile(fixture, JSON.stringify({goal_id: goal, display_name: "Synthetic revision reading", events}));
+  execFileSync(resolveTestPython(), ["-c", `
+import json, sys
+from pathlib import Path
+from loopx.capabilities.explore.result_log import build_explore_node_event, build_explore_finding_event
+path = Path(sys.argv[1]); capture = json.loads(path.read_text())
+rows = []
+for source in capture['events']:
+    row = dict(source)
+    kind, result = row.pop('event_kind'), row.pop('result_id')
+    row.pop('schema_version'); row.pop('event_id')
+    rows.append(build_explore_node_event(node_id=result, **row) if kind == 'node'
+        else build_explore_finding_event(finding_id=result, **row))
+capture['events'] = rows
+path.write_text(json.dumps(capture))
+`, fixture], {cwd: repoRoot});
+  const capture = JSON.parse(await readFile(fixture, "utf8"));
+  const ids = Object.fromEntries(events.map((row, index) => [row.event_id, capture.events[index].event_id]));
+  let owner, page;
+  try {
+    owner = await startHistoryOwner(fixture);
+    page = await browser.newPage({viewport: {width: 1440, height: 900}, timezoneId: "UTC"});
+    await page.addInitScript(() => localStorage.setItem("loopx-pw-locale", "zh-CN"));
+    const url = `${owner.base}/chat/?goalId=${goal}&view=research&statusUrl=%2Fstatus.json`;
+    for (const width of [1440, 390]) {
+      await page.setViewportSize({width, height: 900});
+      await page.goto(url, {waitUntil: "domcontentloaded"});
+      const history = page.locator(".research-history"), reader = history.locator(".research-history-detail");
+      await history.getByRole("status").filter({hasText: "9 / 9"}).waitFor();
+      const middle = history.getByRole("button", {name: /^中段 ·/});
+      await middle.click();
+      assert.match(await middle.getAttribute("aria-label"), /来源记为确认 0.*暂定结论 2/);
+      const point = history.locator('.research-timeline [data-research-nodes~="question"]');
+      assert.equal((await point.getAttribute("data-research-nodes")).split(" ").length > 1, width === 390,
+        "Desktop opens a point; narrow screens retain the nearby-point collection");
+      await point.click();
+      if (width === 390) await reader.locator('[data-research-node="question"] > button').click();
+      const body = reader.locator(".research-recorded-finding");
+      await body.waitFor();
+      await page.screenshot({path: resolve(outputDir, `revised-finding-${width}.png`), animations: "disabled"});
+      assert.match(await body.innerText(), /Middle tentative judgment.*暂定.*MIDDLE-ORIGINAL/s);
+      assert.doesNotMatch(await body.innerText(), /LATE-CONFIRMED/);
+      assert.equal(new URL(page.url()).searchParams.get("research_event"), ids["middle-event"]);
+      await page.reload({waitUntil: "domcontentloaded"});
+      await body.getByText("MIDDLE-ORIGINAL: evidence is still uncertain.", {exact: true}).waitFor();
+      assert.match(await body.locator("small").innerText(), /09:00.*暂定/);
+      const picker = reader.getByRole("combobox", {name: "选择问题结论"});
+      assert.equal(await picker.locator("option").count(), 3, "Both versions of one finding remain selectable");
+      await picker.selectOption(ids["late-event"]);
+      await body.getByText("LATE-CONFIRMED: later evidence changes the conclusion.", {exact: true}).waitFor();
+      assert.match(await body.locator("small").innerText(), /18:00.*来源记为确认/);
+      await page.goBack();
+      await body.getByText("MIDDLE-ORIGINAL: evidence is still uncertain.", {exact: true}).waitFor();
+      await page.goForward();
+      await body.getByText("LATE-CONFIRMED: later evidence changes the conclusion.", {exact: true}).waitFor();
+      await page.goBack();
+      await body.getByText("MIDDLE-ORIGINAL: evidence is still uncertain.", {exact: true}).waitFor();
+      const exact = new URL(page.url()); exact.searchParams.set("research_event", "missing-event");
+      await page.goto(exact.href, {waitUntil: "domcontentloaded"});
+      await reader.getByRole("status").filter({hasText: "此记录中找不到所选结论"}).waitFor();
+      assert.equal(await body.count(), 0, "An absent exact version cannot silently borrow a later one");
+      exact.searchParams.delete("research_event");
+      await page.goto(exact.href, {waitUntil: "domcontentloaded"});
+      await body.getByText("LATE-CONFIRMED: later evidence changes the conclusion.", {exact: true}).waitFor();
+      assert.equal(new URL(page.url()).searchParams.get("research_event"), ids["late-event"], "Existing finding-id links still select the current version");
+      assert(await page.evaluate(() => document.documentElement.scrollWidth <= innerWidth + 1));
+    }
+  } finally {if (page) await page.close(); if (owner) await owner.close(); await rm(directory, {recursive: true, force: true});}
+}
+
 // Whole-page comparison pressure: repeated conditions must not bury the next
 // decision, while its exact original finding remains one keyboard action away.
 async function readDecisionTrail(browser) {
@@ -223,6 +309,35 @@ Path(sys.argv[1]).write_text(json.dumps({'goal_id': goal, 'display_name': 'Synth
     await page.goto(`${owner.base}/chat/?goalId=${owner.goal_id}&view=research&statusUrl=%2Fstatus.json`, {waitUntil: 'domcontentloaded'});
     const history = page.locator('.research-history');
     await history.getByRole('status').filter({hasText: '24 / 24'}).waitFor();
+    const readLatePhase = async (locale, size) => {
+      const late = history.getByRole('button', {name: locale === 'zh-CN' ? /^后段 ·/ : /^Late ·/});
+      await late.focus();
+      await late.press('Enter');
+      assert.equal(await late.getAttribute('aria-pressed'), 'true');
+      await page.screenshot({path: resolve(outputDir, 'recorded-phase-' + size + '-' + locale + '.png'), animations: 'disabled'});
+      assert.equal(await history.locator('[data-research-nodes~="question-2"]:not(.is-dimmed)').count(), 1,
+        'A question with a late record stays highlighted at its earlier first record');
+      assert.equal(await history.locator('[data-research-nodes~="question-3"].is-dimmed').count(), 1,
+        'A question with no records in the selected phase stays dimmed');
+      assert.match(await late.getAttribute('aria-label'), locale === 'zh-CN' ? /2 个有记录的研究项/ : /2 research items with records/);
+      await late.press('Enter');
+    };
+    await readLatePhase('zh-CN', 'desktop');
+    const middle = history.getByRole('button', {name: /^中段 ·/});
+    await middle.press('Enter');
+    await history.locator('.research-timeline [data-research-nodes~="question-1"]').click();
+    const phaseDetail = history.locator('.research-history-detail');
+    await phaseDetail.locator('[data-research-node="question-1"] > button').click();
+    const phaseCapture = JSON.parse(await readFile(fixture, "utf8"));
+    const phaseEventId = id => phaseCapture.events.find(event => event.result_id === id).event_id;
+    const phaseFinding = phaseDetail.getByRole('combobox', {name: '选择问题结论'});
+    assert.equal(await phaseFinding.inputValue(), phaseEventId('decision-1-2'), 'Opening a highlighted question starts with the last finding recorded in the selected period');
+    await page.screenshot({path: resolve(outputDir, 'recorded-phase-finding-desktop.png'), animations: 'disabled'});
+    await phaseFinding.selectOption(phaseEventId('decision-1-4'));
+    assert.equal(new URL(page.url()).searchParams.get('research_finding'), 'decision-1-4', 'An explicit finding outside the selected period remains readable');
+    await phaseDetail.press('Escape');
+    await phaseDetail.press('Escape');
+    await middle.press('Enter');
     const trail = history.locator('.research-trail');
     const group = trail.locator('.research-trail-question').first();
     const assertReturn = async control => {
@@ -251,6 +366,7 @@ Path(sys.argv[1]).write_text(json.dumps({'goal_id': goal, 'display_name': 'Synth
       await page.evaluate(value => localStorage.setItem('loopx-pw-locale', value), locale);
       await page.reload({waitUntil: 'domcontentloaded'});
       await history.getByRole('status').filter({hasText: '24 / 24'}).waitFor();
+      await readLatePhase(locale, 'phone');
       const row = group.locator('[data-research-decision]').first();
       assert.match(await row.innerText(), locale === 'zh-CN' ? /停止 2.*保留 3/s : /Stopped 2.*Retained 3/s);
       await row.scrollIntoViewIfNeeded();
@@ -357,6 +473,7 @@ export const researchHistoryScenario = {
   async run({browser, collectCoverage, url}) {
     await readElapsedTimePrecision(browser);
     await readDecisionTrail(browser);
+    await readRevisedFinding(browser);
     // The ordinary journey uses the real source verifier and HTTP owner, with
     // no intercepted analysis response and no analysis process or Goal writes.
     const nativeOwner = await startHistoryOwner(resolve(repoRoot, "apps/presentation/dashboard/src/data/fixtures/research-native-readback.json"));
@@ -1279,7 +1396,7 @@ Path(sys.argv[1]).write_text(json.dumps({'goal_id':goal,'display_name':'Syntheti
         await detail.locator('[data-research-node="hit-6"] button').click();
         assert.equal(await history.locator('.research-history-canvas').evaluate(e=>e.getBoundingClientRect().width),widthBefore,'Reading never squeezes the whole-history graph');
         assert.equal(await detail.locator('.research-recorded-finding').count(),1,'A question reads one complete finding at a time');
-        await detail.getByRole('combobox',{name:'选择问题结论',exact:true}).selectOption('negative');
+        await detail.getByRole('combobox',{name:'选择问题结论',exact:true}).selectOption({index: 0});
         await detail.getByText('实际执行与资源观测', {exact:true}).click();
         assert(await detail.getByText('scheduler → mask-selection', {exact:true}).isVisible());
         assert(await detail.getByText('未测量', {exact:true}).isVisible(), 'Unknown iterations must not become zero');
diff --git a/loopx/control_plane/presentation/explore_timeline.ts b/loopx/control_plane/presentation/explore_timeline.ts
index 22c2d97e10..77bca488fb 100644
--- a/loopx/control_plane/presentation/explore_timeline.ts
+++ b/loopx/control_plane/presentation/explore_timeline.ts
@@ -52,7 +52,7 @@ export type TimelineFinding = {event: ExploreHistoryEvent; at: number | null; se
 export type TimelineBin = {start: number; end: number; events: number; nodes: number; labels: Record<string, number>; decisions: Record<string, number>};
 export type TimelinePhase = {index: number; start: number; end: number; nodes: number; findings: number; labels: Record<string, number>; decisions: Record<string, number>; lastDecision: TimelineFinding | null};
 export type TimelineRoute = {id: string; nodeIds: string[]; first: number | null; last: number | null};
-export type TimelineNode = {node: ExploreHistoryNode; first: number | null; last: number | null; label: string; routeId: string | null};
+export type TimelineNode = {node: ExploreHistoryNode; first: number | null; last: number | null; label: string; routeId: string | null; recordedPhases: Set<number>};
 export type ExploreTimeline = {
   start: number | null; end: number | null;
   bins: TimelineBin[]; phases: TimelinePhase[];
@@ -110,6 +110,21 @@ export function exploreTimelinePhaseAt(phases: readonly TimelinePhase[], at: num
   return index < 0 ? null : index;
 }
 
+/** Select the original event in this reading period, including a finding that
+ * was revised later. A backfill does not become the latest record time. */
+export function latestExploreFindingInPhase(timeline: ExploreTimeline, nodeId: string, phase: number): ExploreHistoryEvent | undefined {
+  let latest: ExploreHistoryEvent | undefined;
+  let latestAt = -Infinity;
+  for (const {event: finding, at} of timeline.findings) {
+    if (finding.node_id !== nodeId) continue;
+    if (at !== null && at >= latestAt && exploreTimelinePhaseAt(timeline.phases, at) === phase) {
+      latest = finding;
+      latestAt = at;
+    }
+  }
+  return latest;
+}
+
 /** Keep every recorded decision, including repeated attempts and historical backfills. */
 export function selectExploreTimelineDecisions(timeline: ExploreTimeline, phase: number | null): TimelineFinding[] {
   return [...timeline.decisions].reverse()
@@ -159,7 +174,7 @@ export function buildExploreTimeline(nodes: readonly ExploreHistoryNode[], edges
   for (const node of nodes) {
     const stamps = [...node.updates, ...node.findings].map(event => time(event.recorded_at)).filter((at): at is number => at !== null);
     const label = node.findings.at(-1)?.status ?? "";
-    timelineNodes.set(node.id, {node, first: stamps.length ? Math.min(...stamps) : null, last: stamps.length ? Math.max(...stamps) : null, label, routeId: null});
+    timelineNodes.set(node.id, {node, first: stamps.length ? Math.min(...stamps) : null, last: stamps.length ? Math.max(...stamps) : null, label, routeId: null, recordedPhases: new Set()});
   }
   const routes: TimelineRoute[] = [];
   const singles: string[] = [];
@@ -183,8 +198,22 @@ export function buildExploreTimeline(nodes: readonly ExploreHistoryNode[], edges
   const phaseCount = span >= MIN_THIRDS_SPAN_MS ? 3 : 1;
   const phases: TimelinePhase[] = span ? Array.from({length: phaseCount}, (_, index) => ({index, start: start! + span * index / phaseCount, end: start! + span * (index + 1) / phaseCount, nodes: 0, findings: 0, labels: {}, decisions: {}, lastDecision: null})) : [];
   const slot = <T,>(items: T[], at: number) => items[Math.min(items.length - 1, Math.floor((at - start!) / span * items.length))]!;
-  for (const event of events) { const at = time(event.recorded_at); if (at !== null && bins.length) slot(bins, at).events++; }
-  for (const item of timelineNodes.values()) if (item.first !== null && bins.length) { slot(bins, item.first).nodes++; slot(phases, item.first).nodes++; }
+  for (const event of events) {
+    const at = time(event.recorded_at);
+    if (at === null || !bins.length) continue;
+    slot(bins, at).events++;
+    // Count each recorded item once per phase, including later findings on
+    // earlier items. Edges alone do not make an item active in that phase.
+    const node = event.event_kind === "node" ? timelineNodes.get(event.result_id)
+      : event.event_kind === "finding" ? timelineNodes.get(event.node_id) : undefined;
+    if (!node) continue;
+    const phase = slot(phases, at);
+    if (!node.recordedPhases.has(phase.index)) {
+      node.recordedPhases.add(phase.index);
+      phase.nodes++;
+    }
+  }
+  for (const item of timelineNodes.values()) if (item.first !== null && bins.length) slot(bins, item.first).nodes++;
   for (const item of findings) {
     if (item.at === null || !bins.length) continue;
     const bin = slot(bins, item.at), phase = slot(phases, item.at);
diff --git a/tests/control_plane_ts/explore_history.test.ts b/tests/control_plane_ts/explore_history.test.ts
index e9350a7604..9f2e1ac452 100644
--- a/tests/control_plane_ts/explore_history.test.ts
+++ b/tests/control_plane_ts/explore_history.test.ts
@@ -161,7 +161,7 @@ test("elapsed ticks retain both ends of a same-day capture and reserve space for
 });
 
 test("phase reading retains successive decisions for one question, including a late backfill", async () => {
-  const {buildExploreTimeline, exploreTimelinePhaseAt, selectExploreTimelineDecisions} = await import("../../loopx/control_plane/presentation/explore_timeline.ts");
+  const {buildExploreTimeline, exploreTimelinePhaseAt, latestExploreFindingInPhase, selectExploreTimelineDecisions} = await import("../../loopx/control_plane/presentation/explore_timeline.ts");
   const finding = (id: string, at: string, outcome: string) => event({event_id: id, event_kind: "finding", result_id: id, node_id: "route", recorded_at: at, status: "tentative",
     summary: `Input revision: v1 Applicability: this input Observation: measured Interpretation: Outcome: ${outcome} changed: - ${id}`});
   const rows = [event(), finding("early", "2026-01-01T01:00:00Z", "continue"),
@@ -170,13 +170,34 @@ test("phase reading retains successive decisions for one question, including a l
   const view = projectExploreHistory(rows, goal), timeline = buildExploreTimeline(view.nodes, view.edges, view.events);
   assert.deepEqual(selectExploreTimelineDecisions(timeline, 0).map(item => item.event.event_id), ["early-stop", "backfill", "early"]);
   assert.deepEqual(selectExploreTimelineDecisions(timeline, null).map(item => item.sections!.decision!.outcome), ["wait", "stop", "no_change", "continue"]);
+  assert.deepEqual(timeline.phases.map(phase => phase.nodes), [1, 0, 1], "A late finding keeps the original question active without adding a new one");
+  const original = timeline.nodes.get("route")!;
+  assert.deepEqual([...original.recordedPhases], [0, 2]);
+  assert.equal(original.first, timeline.start, "Later activity does not move the question on the axis");
   assert.equal(timeline.phases[0]!.lastDecision!.event.event_id, "early-stop");
   assert.equal(exploreTimelinePhaseAt(timeline.phases, timeline.phases[1]!.start), 1, "a boundary belongs to one reading group");
   assert.equal(exploreTimelinePhaseAt(timeline.phases, timeline.end), 2);
   assert.equal(exploreTimelinePhaseAt(timeline.phases, null), null, "missing record time remains unknown");
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 0)?.event_id, "early-stop", "The default is the last recorded finding in this period, not the last append");
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 1), undefined, "Do not infer a finding for an empty period");
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 2)?.event_id, "late", "The last endpoint remains included");
   assert.equal(view.nodes[0]!.latest.status, "open", "display-time sorting cannot rewrite canonical node state");
 });
 
+test("period reading selects the original finding event before a same-id revision", async () => {
+  const {buildExploreTimeline, latestExploreFindingInPhase} = await import("../../loopx/control_plane/presentation/explore_timeline.ts");
+  const earlier = event({event_id: "tentative-event", event_kind: "finding", result_id: "revised-finding", node_id: "route",
+    recorded_at: "2026-01-01T09:00:00Z", status: "tentative", summary: "The middle-period observation is still uncertain"});
+  const later = {...earlier, event_id: "confirmed-event", recorded_at: "2026-01-01T18:00:00Z", status: "confirmed", summary: "Later evidence confirms a different conclusion"};
+  const view = projectExploreHistory([event(), earlier, later], goal);
+  const timeline = buildExploreTimeline(view.nodes, view.edges, view.events);
+  assert.equal(view.nodes[0]!.findings[0]!.event_id, later.event_id, "Canonical current state remains append-owned");
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 1)?.event_id, earlier.event_id);
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 1)?.status, "tentative");
+  assert.equal(latestExploreFindingInPhase(timeline, "route", 2)?.event_id, later.event_id);
+  assert.equal(latestExploreFindingInPhase(timeline, "missing", 1), undefined);
+});
+
 test("coincident and nearby records remain accessible without overlapping 44px targets", async () => {
   const {buildExploreTimeline, groupExploreTimelinePoints} = await import("../../loopx/control_plane/presentation/explore_timeline.ts");
   const rows = Array.from({length: 25}, (_, index) => event({event_id: `point-${index}`, result_id: `q-${index}`,