diff --git a/docs/api/openapi.yaml b/docs/api/openapi.yaml
index 05f6899fd..051227ea3 100644
--- a/docs/api/openapi.yaml
+++ b/docs/api/openapi.yaml
@@ -16244,7 +16244,7 @@ paths:
         Cookie or wildcard Bearer, own record only — same refusal under a switch as the answers route. Rate-limited to
         10 restarts per 10 minutes per account.
       requestBody:
-        required: true
+        required: false
         content:
           application/json:
             schema:
diff --git a/src/app/api/onboarding/answers/route.ts b/src/app/api/onboarding/answers/route.ts
index ac502bea3..d8cc35898 100644
--- a/src/app/api/onboarding/answers/route.ts
+++ b/src/app/api/onboarding/answers/route.ts
@@ -51,7 +51,7 @@ const RATE_WINDOW_MS = 10 * 60 * 1000;
 
 export const PATCH = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth();
-  annotate({ action: { name: "onboarding.answer.save" } });
+  annotate({ action: { name: "onboarding.needs.save" } });
 
   const rl = await checkRateLimit(
     `onboarding-answers:${user.id}`,
@@ -60,7 +60,7 @@ export const PATCH = apiHandler(async (request: NextRequest) => {
   );
   if (!rl.allowed) {
     annotate({
-      action: { name: "onboarding.answer.save" },
+      action: { name: "onboarding.needs.save" },
       meta: { outcome: "rate_limited" },
     });
     return apiError("Too many onboarding writes, try again later", 429, {
@@ -76,7 +76,7 @@ export const PATCH = apiHandler(async (request: NextRequest) => {
   const parsed = onboardingAnswerSchema.safeParse(body);
   if (!parsed.success) {
     annotate({
-      action: { name: "onboarding.answer.save" },
+      action: { name: "onboarding.needs.save" },
       meta: { outcome: "validation_failed" },
     });
     return returnAllZodIssues(parsed.error, 422, {
@@ -175,7 +175,7 @@ export const PATCH = apiHandler(async (request: NextRequest) => {
   }
 
   annotate({
-    action: { name: "onboarding.answer.save" },
+    action: { name: "onboarding.needs.save" },
     meta: {
       step: answer.step,
       status: answer.status === "skipped" ? "skipped" : "done",
diff --git a/src/app/api/onboarding/complete/route.ts b/src/app/api/onboarding/complete/route.ts
index d4d378072..bff695481 100644
--- a/src/app/api/onboarding/complete/route.ts
+++ b/src/app/api/onboarding/complete/route.ts
@@ -236,7 +236,10 @@ async function completeNeedsFlow(
     where: { userId },
     data: {
       stepsJson: toJson(confirmed),
-      completedAt: now,
+      // Stamped once. The derivation is latched and the stamp should be too,
+      // or a replay of the confirm quietly moves the instant the setup
+      // finished at.
+      completedAt: record.completedAt ?? now,
       ...(derived ? { modulesDerivedAt: now } : {}),
     },
     select: ONBOARDING_RECORD_SELECT,
diff --git a/src/lib/onboarding/__tests__/needs.test.ts b/src/lib/onboarding/__tests__/needs.test.ts
index 02ad9b7d1..d3ff3e666 100644
--- a/src/lib/onboarding/__tests__/needs.test.ts
+++ b/src/lib/onboarding/__tests__/needs.test.ts
@@ -222,6 +222,27 @@ describe("applyOnboardingAnswer", () => {
   });
 });
 
+describe("applyOnboardingAnswer and the two list answers", () => {
+  it("stores the list de-duplicated, so the column holds what the reader returns", () => {
+    const next = applyOnboardingAnswer(
+      blank(),
+      {
+        step: "areas",
+        areas: ["sleep", "sleep", "labs"],
+      },
+      AT,
+    );
+    expect(next.needs.areas).toEqual(["sleep", "labs"]);
+
+    const sources = applyOnboardingAnswer(
+      blank(),
+      { step: "sources", sources: ["oura", "oura", "manual"] },
+      AT,
+    );
+    expect(sources.needs.sources).toEqual(["oura", "manual"]);
+  });
+});
+
 describe("isOnboardingSettled", () => {
   const settled: OnboardingStateDto = {
     steps: ONBOARDING_STEP_IDS.map((id) => ({ id, status: "done" as const })),
diff --git a/src/lib/onboarding/needs-apply.ts b/src/lib/onboarding/needs-apply.ts
index 2c62ef99c..293448d5c 100644
--- a/src/lib/onboarding/needs-apply.ts
+++ b/src/lib/onboarding/needs-apply.ts
@@ -27,6 +27,15 @@ export interface OnboardingRecordState {
   firstResult: OnboardingFirstResult | null;
 }
 
+/**
+ * The two list answers are stored as given, and a client that sends the same
+ * chip twice would otherwise leave the column holding something the reader
+ * never returns — `parseOnboardingNeeds` de-duplicates on the way out.
+ */
+function unique<T>(values: readonly T[]): T[] {
+  return [...new Set(values)];
+}
+
 function withStatus(
   steps: readonly OnboardingStepState[],
   id: OnboardingStepId,
@@ -63,7 +72,11 @@ export function applyOnboardingAnswer(
         needs: { ...state.needs, recordTarget: input.recordTarget },
       };
     case "areas":
-      return { ...state, steps, needs: { ...state.needs, areas: input.areas } };
+      return {
+        ...state,
+        steps,
+        needs: { ...state.needs, areas: unique(input.areas) },
+      };
     case "medication":
       return {
         ...state,
@@ -74,7 +87,7 @@ export function applyOnboardingAnswer(
       return {
         ...state,
         steps,
-        needs: { ...state.needs, sources: input.sources },
+        needs: { ...state.needs, sources: unique(input.sources) },
       };
     case "visit":
       return { ...state, steps, needs: { ...state.needs, visit: input.visit } };
diff --git a/src/lib/openapi/routes/onboarding.ts b/src/lib/openapi/routes/onboarding.ts
index 16f0443df..f023d8be4 100644
--- a/src/lib/openapi/routes/onboarding.ts
+++ b/src/lib/openapi/routes/onboarding.ts
@@ -285,7 +285,9 @@ export const onboardingPaths: NonNullable<ZodOpenApiObject["paths"]> = {
       description:
         "\"Set up again\", from Settings. Puts the nine steps back to `pending`, clears the flow's own completion stamp, and clears the derivation marker so the next `POST /api/onboarding/complete` may derive a module map again.\n\nIt writes no module state at all: the ordering-versus-removal decision says a re-run never turns off a module somebody turned on by hand, and the protection against the second derivation lives in the merge rather than here. It also keeps the answers, as the prefill for the re-run, keeps a first result that really happened, and leaves the account payload's `onboardingCompletedAt` alone so nobody is pushed back through the first-run redirect.\n\nCookie or wildcard Bearer, own record only — same refusal under a switch as the answers route. Rate-limited to 10 restarts per 10 minutes per account.",
       requestBody: {
-        required: true,
+        // The route accepts an absent body and treats it as `{}`; the schema
+        // is strict, so a body that carries anything is a 422.
+        required: false,
         content: { "application/json": { schema: onboardingRestartRequest } },
       },
       responses: {
diff --git a/tests/integration/onboarding-needs.test.ts b/tests/integration/onboarding-needs.test.ts
index 03296d1f4..35c6f37e9 100644
--- a/tests/integration/onboarding-needs.test.ts
+++ b/tests/integration/onboarding-needs.test.ts
@@ -340,6 +340,8 @@ describe("POST /api/onboarding/complete", () => {
     // Somebody changes their mind in Settings, then the confirm screen is
     // replayed. The second call must leave that decision alone: the latch is
     // what stops a questionnaire from re-applying itself over a later choice.
+    // The completion instant is latched with it — a replay does not move the
+    // moment the setup finished at.
     await getPrismaClient().user.update({
       where: { id: user.id },
       data: { modulePreferencesJson: { ...derived, labs: false } },
@@ -347,6 +349,7 @@ describe("POST /api/onboarding/complete", () => {
     const second = await postComplete();
     expect(second.status).toBe(200);
     expect((await modulePrefs(user.id)).labs).toBe(false);
+    expect((await readState(second)).completedAt).toBe(state.completedAt);
   });
 
   it("never switches off a module the person switched on by hand", async () => {