diff --git a/src/web-server/routes/proxy-routes.ts b/src/web-server/routes/proxy-routes.ts
index 636fe5d8..b4cc3f68 100644
--- a/src/web-server/routes/proxy-routes.ts
+++ b/src/web-server/routes/proxy-routes.ts
@@ -11,6 +11,7 @@ import { Router, Request, Response } from 'express';
 import { loadOrCreateUnifiedConfig, saveUnifiedConfig } from '../../config/unified-config-loader';
 import { testConnection } from '../../cliproxy/remote-proxy-client';
 import { isProxyRunning } from '../../cliproxy/services/proxy-lifecycle-service';
+import { DEFAULT_BACKEND } from '../../cliproxy/platform-detector';
 import {
   DEFAULT_CLIPROXY_SERVER_CONFIG,
   CliproxyServerConfig,
@@ -73,7 +74,7 @@ router.put('/', async (req: Request, res: Response) => {
 router.get('/backend', async (_req: Request, res: Response) => {
   try {
     const config = await loadOrCreateUnifiedConfig();
-    res.json({ backend: config.cliproxy?.backend ?? 'plus' });
+    res.json({ backend: config.cliproxy?.backend ?? DEFAULT_BACKEND });
   } catch (error) {
     console.error('[cliproxy-server-routes] Failed to load backend config:', error);
     res.status(500).json({ error: 'Failed to load backend config' });
@@ -99,7 +100,7 @@ router.put('/backend', async (req: Request, res: Response) => {
 
     // Check if proxy is running - warn about restart requirement
     const config = await loadOrCreateUnifiedConfig();
-    const currentBackend = config.cliproxy?.backend ?? 'plus';
+    const currentBackend = config.cliproxy?.backend ?? DEFAULT_BACKEND;
     if (currentBackend !== backend && isProxyRunning() && !force) {
       res.status(409).json({
         error: 'Proxy is running. Stop proxy first or use force=true to change backend.',
diff --git a/ui/src/components/cliproxy/cliproxy-header.tsx b/ui/src/components/cliproxy/cliproxy-header.tsx
index 956d37ca..6b5bb51a 100644
--- a/ui/src/components/cliproxy/cliproxy-header.tsx
+++ b/ui/src/components/cliproxy/cliproxy-header.tsx
@@ -15,6 +15,7 @@ interface VersionInfo {
   currentVersion: string;
   isStable: boolean;
   stabilityMessage?: string;
+  backendLabel?: string;
 }
 
 interface LoginButtonProps {
@@ -127,6 +128,7 @@ export function CliproxyHeader({
             currentVersion: data.currentVersion,
             isStable: data.isStable,
             stabilityMessage: data.stabilityMessage,
+            backendLabel: data.backendLabel,
           });
         }
       })
@@ -157,7 +159,9 @@ export function CliproxyHeader({
       {/* Top row: Title and Login Buttons */}
       <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-4">
         <div>
-          <h1 className="text-2xl font-bold tracking-tight">CLIProxy Plus</h1>
+          <h1 className="text-2xl font-bold tracking-tight">
+            {versionInfo?.backendLabel ?? 'CLIProxy'}
+          </h1>
           <p className="text-sm text-muted-foreground mt-1">CCS-level account management</p>
         </div>
 
diff --git a/ui/src/components/cliproxy/cliproxy-stats-overview.tsx b/ui/src/components/cliproxy/cliproxy-stats-overview.tsx
index e3f114d2..e4668e80 100644
--- a/ui/src/components/cliproxy/cliproxy-stats-overview.tsx
+++ b/ui/src/components/cliproxy/cliproxy-stats-overview.tsx
@@ -27,6 +27,7 @@ import {
 } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import { useCliproxyStats, useCliproxyStatus } from '@/hooks/use-cliproxy-stats';
+import { useCliproxyUpdateCheck } from '@/hooks/use-cliproxy';
 import { usePrivacy, PRIVACY_BLUR_CLASS } from '@/contexts/privacy-context';
 
 interface CliproxyStatsOverviewProps {
@@ -37,6 +38,8 @@ export function CliproxyStatsOverview({ className }: CliproxyStatsOverviewProps)
   const { privacyMode } = usePrivacy();
   const { data: status, isLoading: statusLoading } = useCliproxyStatus();
   const { data: stats, isLoading: statsLoading, error } = useCliproxyStats(status?.running);
+  const { data: updateCheck } = useCliproxyUpdateCheck();
+  const backendLabel = updateCheck?.backendLabel ?? 'CLIProxy';
 
   const isLoading = statusLoading || (status?.running && statsLoading);
 
@@ -71,7 +74,7 @@ export function CliproxyStatsOverview({ className }: CliproxyStatsOverviewProps)
               Session Statistics
             </h2>
             <p className="text-sm text-muted-foreground">
-              Real-time usage metrics from CLIProxy Plus
+              Real-time usage metrics from {backendLabel}
             </p>
           </div>
           <Badge variant="secondary" className="w-fit gap-1.5">
@@ -146,7 +149,9 @@ export function CliproxyStatsOverview({ className }: CliproxyStatsOverviewProps)
             <Activity className="h-5 w-5" />
             Session Statistics
           </h2>
-          <p className="text-sm text-muted-foreground">Real-time usage metrics from CLIProxyAPI</p>
+          <p className="text-sm text-muted-foreground">
+            Real-time usage metrics from {backendLabel}
+          </p>
         </div>
         <Badge
           variant="outline"
diff --git a/ui/src/components/cliproxy/overview/model-preferences-grid.tsx b/ui/src/components/cliproxy/overview/model-preferences-grid.tsx
index 62630fce..8bdd8f81 100644
--- a/ui/src/components/cliproxy/overview/model-preferences-grid.tsx
+++ b/ui/src/components/cliproxy/overview/model-preferences-grid.tsx
@@ -8,7 +8,7 @@ import { Card, CardContent, CardHeader, CardTitle, CardDescription } from '@/com
 import { Badge } from '@/components/ui/badge';
 import { Skeleton } from '@/components/ui/skeleton';
 import { Cpu, AlertCircle } from 'lucide-react';
-import { useCliproxyModels } from '@/hooks/use-cliproxy';
+import { useCliproxyModels, useCliproxyUpdateCheck } from '@/hooks/use-cliproxy';
 import { cn } from '@/lib/utils';
 
 /** Category display configuration */
@@ -70,6 +70,8 @@ function EmptyModelsState() {
 
 export function ModelPreferencesGrid() {
   const { data: modelsData, isLoading, isError } = useCliproxyModels();
+  const { data: updateCheck } = useCliproxyUpdateCheck();
+  const backendLabel = updateCheck?.backendLabel ?? 'CLIProxy';
 
   // Sort categories by model count
   const sortedCategories = useMemo(() => {
@@ -102,7 +104,7 @@ export function ModelPreferencesGrid() {
           </Badge>
         </CardTitle>
         <CardDescription>
-          Models available through CLIProxy Plus, grouped by provider
+          Models available through {backendLabel}, grouped by provider
         </CardDescription>
       </CardHeader>
       <CardContent>
diff --git a/ui/src/components/layout/app-sidebar.tsx b/ui/src/components/layout/app-sidebar.tsx
index dc5da3b4..a2cf8040 100644
--- a/ui/src/components/layout/app-sidebar.tsx
+++ b/ui/src/components/layout/app-sidebar.tsx
@@ -30,6 +30,7 @@ import {
 } from '@/components/ui/sidebar';
 import { CcsLogo } from '@/components/shared/ccs-logo';
 import { useSidebar } from '@/hooks/use-sidebar';
+import { useCliproxyUpdateCheck } from '@/hooks/use-cliproxy';
 import { Collapsible, CollapsibleContent, CollapsibleTrigger } from '@/components/ui/collapsible';
 import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip';
 
@@ -87,6 +88,18 @@ export function AppSidebar() {
   const location = useLocation();
   const navigate = useNavigate();
   const { state } = useSidebar();
+  const { data: updateCheck } = useCliproxyUpdateCheck();
+
+  // Dynamic label for CLIProxy based on backend
+  const cliproxyLabel = updateCheck?.backendLabel ?? 'CLIProxy';
+
+  // Helper to get dynamic label (for CLIProxy route)
+  const getItemLabel = (item: { path: string; label: string }) => {
+    if (item.path === '/cliproxy') {
+      return cliproxyLabel;
+    }
+    return item.label;
+  };
 
   // Helper to check if a route is active (exact match)
   const isRouteActive = (path: string) => location.pathname === path;
@@ -122,13 +135,13 @@ export function AppSidebar() {
                           {/* Click navigates to overview AND opens submenu */}
                           <CollapsibleTrigger asChild>
                             <SidebarMenuButton
-                              tooltip={item.label}
+                              tooltip={getItemLabel(item)}
                               isActive={isParentActive(item.children)}
                               onClick={() => navigate(item.path)}
                             >
                               {item.icon && <item.icon className="w-4 h-4" />}
                               <span className="group-data-[collapsible=icon]:hidden">
-                                {item.label}
+                                {getItemLabel(item)}
                               </span>
                               <ChevronRight className="ml-auto transition-transform duration-200 group-data-[state=open]/collapsible:rotate-90 group-data-[collapsible=icon]:hidden" />
                             </SidebarMenuButton>
@@ -155,12 +168,12 @@ export function AppSidebar() {
                       <SidebarMenuButton
                         asChild
                         isActive={isRouteActive(item.path)}
-                        tooltip={item.label}
+                        tooltip={getItemLabel(item)}
                       >
                         <Link to={item.path}>
                           {item.icon && <item.icon className="w-4 h-4" />}
                           <span className="group-data-[collapsible=icon]:hidden flex-1">
-                            {item.label}
+                            {getItemLabel(item)}
                           </span>
                           {item.badge && (
                             <Tooltip>
diff --git a/ui/src/hooks/use-cliproxy.ts b/ui/src/hooks/use-cliproxy.ts
index 3d310f02..dce70f76 100644
--- a/ui/src/hooks/use-cliproxy.ts
+++ b/ui/src/hooks/use-cliproxy.ts
@@ -333,9 +333,40 @@ export function useCliproxyUpdateCheck() {
   return useQuery({
     queryKey: ['cliproxy-update-check'],
     queryFn: () => api.cliproxy.updateCheck(),
-    staleTime: 60 * 60 * 1000, // 1 hour (matches backend cache)
-    refetchInterval: 60 * 60 * 1000, // Refresh every hour
-    refetchOnWindowFocus: false, // Don't refresh on window focus (save API calls)
+    staleTime: 5 * 60 * 1000, // 5 minutes (reduced from 1 hour for faster backend switch response)
+    refetchInterval: 5 * 60 * 1000, // Refresh every 5 minutes
+    refetchOnWindowFocus: true, // Refetch on window focus to catch backend changes
+  });
+}
+
+// ==================== Backend Management ====================
+
+/**
+ * Hook for switching CLIProxy backend (original vs plus)
+ * Invalidates all backend-dependent queries to ensure UI consistency
+ */
+export function useUpdateBackend() {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: ({ backend, force = false }: { backend: 'original' | 'plus'; force?: boolean }) =>
+      api.cliproxyServer.updateBackend(backend, force),
+    onSuccess: () => {
+      // Invalidate all queries that depend on backend setting
+      queryClient.invalidateQueries({ queryKey: ['cliproxy-update-check'] });
+      queryClient.invalidateQueries({ queryKey: ['cliproxy-versions'] });
+      queryClient.invalidateQueries({ queryKey: ['proxy-status'] });
+      queryClient.invalidateQueries({ queryKey: ['cliproxy-stats'] });
+      toast.success('Backend updated');
+    },
+    onError: (error: Error) => {
+      // Handle 409 conflict (proxy running)
+      if (error.message.includes('Proxy is running')) {
+        toast.error('Stop the proxy first to change backend');
+      } else {
+        toast.error(error.message);
+      }
+    },
   });
 }
 
diff --git a/ui/src/pages/settings/sections/proxy/index.tsx b/ui/src/pages/settings/sections/proxy/index.tsx
index 275b356f..4c1518f7 100644
--- a/ui/src/pages/settings/sections/proxy/index.tsx
+++ b/ui/src/pages/settings/sections/proxy/index.tsx
@@ -18,8 +18,8 @@ import {
   Box,
   AlertTriangle,
 } from 'lucide-react';
-import { toast } from 'sonner';
 import { useProxyConfig, useRawConfig } from '../../hooks';
+import { useUpdateBackend } from '@/hooks/use-cliproxy';
 import { LocalProxyCard } from './local-proxy-card';
 import { RemoteProxyCard } from './remote-proxy-card';
 import { api } from '@/lib/api-client';
@@ -74,10 +74,10 @@ export default function ProxySection() {
     }
   };
 
-  // Backend state (loaded from API)
+  // Backend state (loaded from API) + mutation hook for proper query invalidation
   const [backend, setBackend] = useState<'original' | 'plus'>('plus');
-  const [backendSaving, setBackendSaving] = useState(false);
   const [hasKiroGhcpVariants, setHasKiroGhcpVariants] = useState(false);
+  const updateBackendMutation = useUpdateBackend();
 
   // Fetch backend setting
   const fetchBackend = useCallback(async () => {
@@ -100,24 +100,18 @@ export default function ProxySection() {
     }
   }, []);
 
-  // Save backend setting
-  const handleBackendChange = async (value: 'original' | 'plus') => {
+  // Save backend setting using mutation hook (invalidates all related queries)
+  const handleBackendChange = (value: 'original' | 'plus') => {
     const previousValue = backend;
-    setBackend(value);
-    setBackendSaving(true);
-    try {
-      await api.cliproxyServer.updateBackend(value);
-    } catch (err) {
-      const errorMessage = err instanceof Error ? err.message : 'Failed to save backend';
-      // Check if error is due to proxy running (409 conflict)
-      if (errorMessage.includes('Proxy is running')) {
-        toast.error('Stop the proxy first to change backend');
+    setBackend(value); // Optimistic update
+    updateBackendMutation.mutate(
+      { backend: value },
+      {
+        onError: () => {
+          setBackend(previousValue); // Rollback on error
+        },
       }
-      console.error('[Proxy] Failed to save backend:', err);
-      setBackend(previousValue);
-    } finally {
-      setBackendSaving(false);
-    }
+    );
   };
 
   // Log when debug mode changes (sanitize sensitive fields)
@@ -140,8 +134,10 @@ export default function ProxySection() {
   useEffect(() => {
     fetchConfig();
     fetchRawConfig();
-    fetchBackend();
-    checkPlusOnlyVariants();
+    // eslint-disable-next-line react-hooks/set-state-in-effect -- Async data fetching on mount is intended
+    void fetchBackend();
+
+    void checkPlusOnlyVariants();
   }, [fetchConfig, fetchRawConfig, fetchBackend, checkPlusOnlyVariants]);
 
   if (loading || !config) {
@@ -253,7 +249,8 @@ export default function ProxySection() {
       <ScrollArea className="flex-1">
         <div className="p-5 space-y-6">
           <p className="text-sm text-muted-foreground">
-            Configure local or remote CLIProxy Plus connection for proxy-based profiles
+            Configure local or remote {backend === 'plus' ? 'CLIProxy Plus' : 'CLIProxy'} connection
+            for proxy-based profiles
           </p>
 
           {/* Mode Toggle - Card based selection */}
@@ -277,7 +274,7 @@ export default function ProxySection() {
                   <span className="font-medium">Local</span>
                 </div>
                 <p className="text-xs text-muted-foreground">
-                  Run CLIProxy Plus binary on this machine
+                  Run {backend === 'plus' ? 'CLIProxy Plus' : 'CLIProxy'} binary on this machine
                 </p>
               </button>
 
@@ -298,7 +295,7 @@ export default function ProxySection() {
                   <span className="font-medium">Remote</span>
                 </div>
                 <p className="text-xs text-muted-foreground">
-                  Connect to a remote CLIProxy Plus server
+                  Connect to a remote {backend === 'plus' ? 'CLIProxy Plus' : 'CLIProxy'} server
                 </p>
               </button>
             </div>
@@ -314,7 +311,7 @@ export default function ProxySection() {
               {/* Plus Backend Card */}
               <button
                 onClick={() => handleBackendChange('plus')}
-                disabled={backendSaving}
+                disabled={updateBackendMutation.isPending}
                 className={`p-4 rounded-lg border-2 text-left transition-all ${
                   backend === 'plus'
                     ? 'border-primary bg-primary/5'
@@ -335,7 +332,7 @@ export default function ProxySection() {
               {/* Original Backend Card */}
               <button
                 onClick={() => handleBackendChange('original')}
-                disabled={backendSaving}
+                disabled={updateBackendMutation.isPending}
                 className={`p-4 rounded-lg border-2 text-left transition-all ${
                   backend === 'original'
                     ? 'border-primary bg-primary/5'