diff --git a/src/providers/github-copilot-auto.ts b/src/providers/github-copilot-auto.ts
index e42347342be..1d927525fb7 100644
--- a/src/providers/github-copilot-auto.ts
+++ b/src/providers/github-copilot-auto.ts
@@ -135,7 +135,10 @@ export async function resolveCopilotAuto(provider: OcxProviderConfig, requestedM
     // control-plane send. That is not a client abort: fall back to the requested model
     // so the dispatch path revalidates the selection and rebuilds on the new account.
     if (error instanceof ProviderOutboundSendCancelledError) {
-      return { provider: transport, modelId: requestedModel, auto: false };
+      // expiresAt 0: this selection was never negotiated. request-transport fences the physical
+      // send on it, so dispatch always renegotiates instead of sending the bare requested model
+      // if the selection becomes current again before the send.
+      return { provider: transport, modelId: requestedModel, auto: false, expiresAt: 0 };
     }
     // Permission discovery is additive for legacy paid configurations. A temporary
     // discovery outage must not turn a previously usable named route into a refusal.
@@ -148,7 +151,7 @@ export async function resolveCopilotAuto(provider: OcxProviderConfig, requestedM
   // new account instead of failing the whole negotiation. A client abort still rejects.
   const fallBackOnSwitch = (error: unknown) => {
     if (!signal?.aborted && error instanceof ProviderOutboundSendCancelledError)
-      return { provider: transport, modelId: requestedModel, auto: false } as const;
+      return { provider: transport, modelId: requestedModel, auto: false, expiresAt: 0 } as const;
     throw error;
   };
   let session: Awaited<ReturnType<typeof requestJson>>;
diff --git a/tests/providers/github-copilot/github-copilot-auto.test.ts b/tests/providers/github-copilot/github-copilot-auto.test.ts
index ef9cf814699..0a6f40a23b1 100644
--- a/tests/providers/github-copilot/github-copilot-auto.test.ts
+++ b/tests/providers/github-copilot/github-copilot-auto.test.ts
@@ -196,7 +196,9 @@ describe("Copilot Auto permissions and negotiation", () => {
       calls++; throw new Error("network unavailable");
     }) as typeof fetch } as OcxProviderConfig;
     expect((await resolveCopilotAuto(provider, "named", parsed)).modelId).toBe("named");
-    expect(calls).toBe(1);
+    // An outage fallback is a usable named route, not a lapsed negotiation: no forced rebuild.
+    expect((await resolveCopilotAuto(provider, "named", parsed)).expiresAt).toBeUndefined();
+    expect(calls).toBe(2);
   });
   for (const cancelAt of ["/models/session", "/models/session/intent"] as const) {
     test(`an authority change during ${cancelAt} also falls back instead of failing negotiation`, async () => {
@@ -214,8 +216,11 @@ describe("Copilot Auto permissions and negotiation", () => {
         if (seen.length === (cancelAt === "/models/session" ? 1 : 2)) allowed = false;
         return allowed;
       };
-      await expect(resolveCopilotAuto(provider, "auto", parsed, undefined, beforeSend))
-        .resolves.toMatchObject({ modelId: "auto", auto: false });
+      const selected = await resolveCopilotAuto(provider, "auto", parsed, undefined, beforeSend);
+      expect(selected).toMatchObject({ modelId: "auto", auto: false });
+      // The fallback was never negotiated. request-transport fences dispatch on expiresAt, so an
+      // already-lapsed value makes dispatch renegotiate even if the selection becomes current again.
+      expect(selected.expiresAt).toBeLessThanOrEqual(Date.now());
       expect(seen.some(path => path.endsWith(cancelAt))).toBe(false);
     });
   }
@@ -227,8 +232,9 @@ describe("Copilot Auto permissions and negotiation", () => {
     await expect(resolveCopilotAuto(provider, "auto", parsed, AbortSignal.abort())).rejects.toThrow();
     // A manual account switch cancels the queued control-plane send. That is not a client
     // abort: the caller revalidates the selection and rebuilds before dispatch.
-    await expect(resolveCopilotAuto(provider, "auto", parsed, undefined, () => false))
-      .resolves.toMatchObject({ modelId: "auto", auto: false });
+    const selected = await resolveCopilotAuto(provider, "auto", parsed, undefined, () => false);
+    expect(selected).toMatchObject({ modelId: "auto", auto: false });
+    expect(selected.expiresAt).toBeLessThanOrEqual(Date.now());
     expect(sends).toBe(0);
   });
 });