diff --git a/src/cliproxy/codex-plan-compatibility.ts b/src/cliproxy/codex-plan-compatibility.ts
index 91a30380..41177e00 100644
--- a/src/cliproxy/codex-plan-compatibility.ts
+++ b/src/cliproxy/codex-plan-compatibility.ts
@@ -66,7 +66,9 @@ export async function reconcileCodexModelForActivePlan(options: {
   }
 
   if (quota.planType === 'free') {
-    updateSettingsModel(settingsPath, fallbackModel, 'codex');
+    updateSettingsModel(settingsPath, fallbackModel, 'codex', {
+      rewriteHaikuModel: (haikuModel) => getFreePlanFallbackCodexModel(haikuModel) ?? haikuModel,
+    });
     console.error(
       info(
         `Codex free plan detected. Switched unsupported model "${normalizeCodexModelId(currentModel)}" ` +
diff --git a/src/cliproxy/services/variant-settings.ts b/src/cliproxy/services/variant-settings.ts
index 4dbca1fc..7c7d2038 100644
--- a/src/cliproxy/services/variant-settings.ts
+++ b/src/cliproxy/services/variant-settings.ts
@@ -290,7 +290,10 @@ export function deleteSettingsFile(settingsPath: string): boolean {
 export function updateSettingsModel(
   settingsPath: string,
   model: string,
-  provider?: CLIProxyProfileName
+  provider?: CLIProxyProfileName,
+  options?: {
+    rewriteHaikuModel?: (model: string) => string;
+  }
 ): void {
   const fileName = path.basename(settingsPath);
   if (fileName.startsWith('composite-')) {
@@ -316,10 +319,13 @@ export function updateSettingsModel(
       settings.env.ANTHROPIC_DEFAULT_OPUS_MODEL = normalizedModel;
       settings.env.ANTHROPIC_DEFAULT_SONNET_MODEL = normalizedModel;
       if (provider === 'codex' && settings.env.ANTHROPIC_DEFAULT_HAIKU_MODEL) {
-        settings.env.ANTHROPIC_DEFAULT_HAIKU_MODEL = canonicalizeModelForProvider(
+        const normalizedHaikuModel = canonicalizeModelForProvider(
           provider,
           settings.env.ANTHROPIC_DEFAULT_HAIKU_MODEL
         );
+        settings.env.ANTHROPIC_DEFAULT_HAIKU_MODEL = options?.rewriteHaikuModel
+          ? options.rewriteHaikuModel(normalizedHaikuModel)
+          : normalizedHaikuModel;
       }
     } else {
       // Clear model settings to use defaults
diff --git a/tests/unit/cliproxy/codex-plan-compatibility-reconcile.test.ts b/tests/unit/cliproxy/codex-plan-compatibility-reconcile.test.ts
index d11d6e6e..b22ac1fa 100644
--- a/tests/unit/cliproxy/codex-plan-compatibility-reconcile.test.ts
+++ b/tests/unit/cliproxy/codex-plan-compatibility-reconcile.test.ts
@@ -7,7 +7,10 @@ afterEach(() => {
   mock.restore();
 });
 
-function createCodexSettingsFixture(): { tmpDir: string; settingsPath: string } {
+function createCodexSettingsFixture(haikuModel: string = 'gpt-5-codex-mini'): {
+  tmpDir: string;
+  settingsPath: string;
+} {
   const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ccs-codex-plan-compat-'));
   const settingsPath = path.join(tmpDir, 'codex.settings.json');
 
@@ -21,7 +24,7 @@ function createCodexSettingsFixture(): { tmpDir: string; settingsPath: string }
           ANTHROPIC_MODEL: 'gpt-5.3-codex',
           ANTHROPIC_DEFAULT_OPUS_MODEL: 'gpt-5.3-codex',
           ANTHROPIC_DEFAULT_SONNET_MODEL: 'gpt-5.3-codex',
-          ANTHROPIC_DEFAULT_HAIKU_MODEL: 'gpt-5-codex-mini',
+          ANTHROPIC_DEFAULT_HAIKU_MODEL: haikuModel,
         },
       },
       null,
@@ -39,7 +42,7 @@ async function importCompatibilityModule(cacheTag: string) {
 
 describe('codex plan compatibility reconcile', () => {
   it('repairs stale paid-only Codex settings for free-plan accounts before launch', async () => {
-    const { tmpDir, settingsPath } = createCodexSettingsFixture();
+    const { tmpDir, settingsPath } = createCodexSettingsFixture('gpt-5.3-codex-spark');
 
     mock.module('../../../src/cliproxy/account-manager', () => ({
       getDefaultAccount: () => ({ id: 'free@example.com' }),
@@ -230,4 +233,54 @@ describe('codex plan compatibility reconcile', () => {
       fs.rmSync(tmpDir, { recursive: true, force: true });
     }
   });
+
+  it('warns and keeps settings unchanged when quota succeeds without a plan type', async () => {
+    const { tmpDir, settingsPath } = createCodexSettingsFixture();
+
+    mock.module('../../../src/cliproxy/account-manager', () => ({
+      getDefaultAccount: () => ({ id: 'missing-plan@example.com' }),
+    }));
+    mock.module('../../../src/cliproxy/quota-fetcher-codex', () => ({
+      fetchCodexQuota: async () => ({
+        success: true,
+        windows: [],
+        coreUsage: { fiveHour: null, weekly: null },
+        planType: null,
+        lastUpdated: Date.now(),
+        accountId: 'missing-plan@example.com',
+      }),
+    }));
+    mock.module('../../../src/cliproxy/quota-response-cache', () => ({
+      getCachedQuota: () => null,
+      setCachedQuota: () => {},
+    }));
+    mock.module('../../../src/utils/ui', () => ({
+      info: (message: string) => message,
+      warn: (message: string) => message,
+    }));
+
+    const errorSpy = spyOn(console, 'error').mockImplementation(() => {});
+
+    try {
+      const { reconcileCodexModelForActivePlan } =
+        await importCompatibilityModule('missing-plan-type');
+
+      await reconcileCodexModelForActivePlan({
+        settingsPath,
+        currentModel: 'gpt-5.3-codex',
+        verbose: false,
+      });
+
+      const settings = JSON.parse(fs.readFileSync(settingsPath, 'utf-8')) as {
+        env: Record<string, string>;
+      };
+      expect(settings.env.ANTHROPIC_MODEL).toBe('gpt-5.3-codex');
+      expect(settings.env.ANTHROPIC_DEFAULT_HAIKU_MODEL).toBe('gpt-5-codex-mini');
+      expect(errorSpy).toHaveBeenCalledWith(
+        'Could not verify Codex plan for model "gpt-5.3-codex". If startup fails with model_not_supported, switch to "gpt-5-codex" via "ccs codex --config".'
+      );
+    } finally {
+      fs.rmSync(tmpDir, { recursive: true, force: true });
+    }
+  });
 });