diff --git a/static/index.html b/static/index.html
index c0fd60197..34195ca38 100644
--- a/static/index.html
+++ b/static/index.html
@@ -219,8 +219,8 @@
       }, { once: true });
     })();
   </script>
-  <link rel="stylesheet" href="/static/style.css?v=20260630emailrace">
-  <link rel="modulepreload" href="/static/app.js?v=20260630emailrace">
+  <link rel="stylesheet" href="/static/style.css?v=20260630modelfallback">
+  <link rel="modulepreload" href="/static/app.js?v=20260630modelfallback">
   <link rel="modulepreload" href="/static/js/chat.js">
   <link rel="modulepreload" href="/static/js/ui.js">
   <link rel="modulepreload" href="/static/js/sessions.js">
@@ -2512,7 +2512,7 @@
 <script type="module" src="/static/js/settings.js"></script>
 <script type="module" src="/static/js/admin.js"></script>
 <script type="module" src="/static/js/assistant.js"></script>
-<script type="module" src="/static/app.js?v=20260630emailrace"></script>  <!-- app.js must be LAST -->
+<script type="module" src="/static/app.js?v=20260630modelfallback"></script>  <!-- app.js must be LAST -->
 <script type="module" src="/static/js/init.js"></script>
 <script type="module" src="/static/js/a11y.js"></script>
 <script nonce="{{CSP_NONCE}}">if('serviceWorker' in navigator){navigator.serviceWorker.register('/static/sw.js').catch(()=>{});}</script>
diff --git a/static/js/modelPicker.js b/static/js/modelPicker.js
index 12fb3479e..53077b73b 100644
--- a/static/js/modelPicker.js
+++ b/static/js/modelPicker.js
@@ -92,6 +92,31 @@ function _modelExists(modelId, url) {
   });
 }
 
+function _firstAvailableModel() {
+  if (!window.modelsModule || !window.modelsModule.getCachedItems) return null;
+  const items = window.modelsModule.getCachedItems() || [];
+  for (const item of items) {
+    if (item.offline) continue;
+    const models = (item.models || []).concat(item.models_extra || []);
+    if (!models.length) continue;
+    return {
+      url: item.url,
+      modelId: models[0],
+      endpointId: item.endpoint_id || '',
+    };
+  }
+  return null;
+}
+
+async function _ensureModelCacheForFallback() {
+  if (!window.modelsModule || !window.modelsModule.getCachedItems) return;
+  const items = window.modelsModule.getCachedItems() || [];
+  if (items.length) return;
+  if (typeof window.modelsModule.refreshModels === 'function') {
+    try { await window.modelsModule.refreshModels(false); } catch (_) {}
+  }
+}
+
 async function _ensureDefaultPendingChat() {
   if (!_deps || _defaultChatPickInFlight) return;
   if (_deps.getCurrentSessionId && _deps.getCurrentSessionId()) return;
@@ -99,12 +124,13 @@ async function _ensureDefaultPendingChat() {
   if (pending && pending.modelId) return;
   _defaultChatPickInFlight = true;
   try {
+    await _ensureModelCacheForFallback();
     let dc = null;
     try {
       const res = await fetch(`${API_BASE}/api/default-chat`, { credentials: 'same-origin' });
       if (res.ok) dc = await res.json();
     } catch (_) {}
-    if (dc && dc.endpoint_url && dc.model) {
+    if (dc && dc.endpoint_url && dc.model && _modelExists(dc.model, dc.endpoint_url)) {
       _deps.setPendingChat({
         url: dc.endpoint_url,
         modelId: dc.model,
@@ -114,15 +140,12 @@ async function _ensureDefaultPendingChat() {
       updateModelPicker();
       return;
     }
-    // No configured default: preserve the old convenience fallback.
-    if (window.modelsModule && window.modelsModule.getCachedItems) {
-      const items = window.modelsModule.getCachedItems();
-      const first = items.find(item => !item.offline && ((item.models || []).length || (item.models_extra || []).length));
-      if (first) {
-        const models = (first.models || []).concat(first.models_extra || []);
-        _deps.setPendingChat({ url: first.url, modelId: models[0], endpointId: first.endpoint_id });
-        updateModelPicker();
-      }
+    // No configured default, or the configured default is gone/offline:
+    // preserve the convenience fallback and keep the picker usable.
+    const fallback = _firstAvailableModel();
+    if (fallback) {
+      _deps.setPendingChat(fallback);
+      updateModelPicker();
     }
   } finally {
     _defaultChatPickInFlight = false;
diff --git a/static/sw.js b/static/sw.js
index 8e8930e9d..3df123bce 100644
--- a/static/sw.js
+++ b/static/sw.js
@@ -7,7 +7,7 @@
 //   - Other static assets (images/fonts/libs): cache-first with bg refresh.
 //   - API / non-GET: never cached.
 // Bump CACHE_NAME whenever the precache list or SW logic changes.
-const CACHE_NAME = 'odysseus-v333';
+const CACHE_NAME = 'odysseus-v334';
 
 // Core shell precached on install so repeat opens are instant without any
 // network wait. Keep this list in sync with the <script type="module"> tags