diff --git a/admin-lehrer/components/grid-editor/useGridEditor.ts b/admin-lehrer/components/grid-editor/useGridEditor.ts
index 9936ddd..a689d98 100644
--- a/admin-lehrer/components/grid-editor/useGridEditor.ts
+++ b/admin-lehrer/components/grid-editor/useGridEditor.ts
@@ -101,16 +101,42 @@ export function useGridEditor(sessionId: string | null) {
     }
   }, [sessionId, buildGrid])
 
-  // Auto-rebuild when IPA or syllable mode changes (skip initial mount)
+  // Auto-rebuild when IPA or syllable mode changes (skip initial mount).
+  // We call the API directly with the new values instead of going through
+  // the buildGrid callback, which may still close over stale state due to
+  // React's asynchronous state batching.
   const initialLoadDone = useRef(false)
   useEffect(() => {
     if (!initialLoadDone.current) {
-      // Mark as initialized once the first grid is loaded
       if (grid) initialLoadDone.current = true
       return
     }
-    // Mode changed after initial load — rebuild
-    buildGrid()
+    if (!sessionId) return
+    const rebuild = async () => {
+      setLoading(true)
+      setError(null)
+      try {
+        const params = new URLSearchParams()
+        params.set('ipa_mode', ipaMode)
+        params.set('syllable_mode', syllableMode)
+        const res = await fetch(
+          `${KLAUSUR_API}/api/v1/ocr-pipeline/sessions/${sessionId}/build-grid?${params}`,
+          { method: 'POST' },
+        )
+        if (!res.ok) {
+          const data = await res.json().catch(() => ({}))
+          throw new Error(data.detail || `HTTP ${res.status}`)
+        }
+        const data: StructuredGrid = await res.json()
+        setGrid(data)
+        setDirty(false)
+      } catch (e) {
+        setError(e instanceof Error ? e.message : String(e))
+      } finally {
+        setLoading(false)
+      }
+    }
+    rebuild()
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [ipaMode, syllableMode])