diff --git a/app/routes/envios.py b/app/routes/envios.py
index 4120cd8..4392c0b 100644
--- a/app/routes/envios.py
+++ b/app/routes/envios.py
@@ -45,8 +45,11 @@ async def erp_sync_now(
 
 
 @router.post("/erp/sync-diagnosticos")
-async def erp_sync_diagnosticos(user: dict = Depends(get_current_user)):
-    """Migra los 12.422 diagnósticos CIE-10 de Firebird → WhatsApp en lotes de 500."""
+async def erp_sync_diagnosticos(
+    user: dict = Depends(get_current_user),
+    start_from: int = Query(default=0, ge=0, description="Índice desde el que reanudar"),
+):
+    """Migra los 12.422 diagnósticos CIE-10 de Firebird → WhatsApp en lotes de 200."""
     try:
         conn = get_connection()
         configs = {row["key"]: row["value"] for row in conn.execute("SELECT * FROM config").fetchall()}
@@ -72,14 +75,14 @@ async def erp_sync_diagnosticos(user: dict = Depends(get_current_user)):
 
         diagnosticos = [{"cod": r["COD_DIAG"], "concepto": r["CONCEPTO"]} for r in (rows or [])]
         total = len(diagnosticos)
-        batch_size = 500
+        batch_size = 200
         url = f"{wa_url}/api/lab/ingest_diagnosticos.php"
         headers = {"Content-Type": "application/json", "X-Lab-Key": wa_key}
 
         insertados = 0
         errores = []
         async with httpx.AsyncClient(timeout=60) as client:
-            for i in range(0, total, batch_size):
+            for i in range(start_from, total, batch_size):
                 lote = diagnosticos[i:i + batch_size]
                 try:
                     resp = await client.post(url, json={"rows": lote}, headers=headers)
diff --git a/app/templates/envios_erp.html b/app/templates/envios_erp.html
index f40d328..e746a31 100644
--- a/app/templates/envios_erp.html
+++ b/app/templates/envios_erp.html
@@ -87,7 +87,7 @@
                         <span class="text-xs text-gray-400">12.422 diagnósticos de Firebird → WhatsApp</span>
                     </div>
                     <div class="p-5 flex flex-wrap items-center gap-4">
-                        <p class="text-sm text-gray-500 flex-1">Ejecutar una vez para poblar la tabla <code class="bg-gray-100 px-1 rounded">cie10_diagnosticos</code> en WhatsApp. Requiere correr la migración SQL primero.</p>
+                        <p class="text-sm text-gray-500 flex-1">Pobla la tabla <code class="bg-gray-100 px-1 rounded">cie10_diagnosticos</code> en WhatsApp. Idempotente — se puede re-ejecutar. Si corta a la mitad, usa "Reanudar" para continuar desde donde quedó.</p>
                         <button id="btn-sync-diag" onclick="ejecutarSyncDiag()"
                             class="flex items-center gap-2 bg-orange-500 hover:bg-orange-600 text-white text-sm font-medium px-4 py-2 rounded-lg transition-colors whitespace-nowrap">
                             <i class="fas fa-upload text-xs"></i> Migrar diagnósticos
@@ -178,26 +178,37 @@ function switchTab(name) {
 const _origenLabel = { manual: 'Manual', tercero: 'Tercero', scheduler: 'Scheduler', automation: 'Automatización' };
 const _modoLabel   = { insertar: 'Solo nuevos', upsert: 'Upsert' };
 
-async function ejecutarSyncDiag() {
+async function ejecutarSyncDiag(startFrom = 0) {
     const btn = document.getElementById('btn-sync-diag');
     const resBox = document.getElementById('sync-diag-result');
     const inner  = document.getElementById('sync-diag-inner');
     btn.disabled = true;
     btn.innerHTML = '<i class="fas fa-spinner fa-spin text-xs"></i> Migrando…';
     resBox.classList.remove('hidden');
-    inner.innerHTML = '<p class="text-sm text-gray-400">Enviando 12.422 diagnósticos en lotes de 500…</p>';
+    inner.innerHTML = `<p class="text-sm text-gray-400">Enviando diagnósticos en lotes de 200${startFrom ? ` (desde #${startFrom.toLocaleString()})` : ''}…</p>`;
     try {
-        const resp = await fetch('/envios/erp/sync-diagnosticos', { method: 'POST' });
+        const url = `/envios/erp/sync-diagnosticos${startFrom ? `?start_from=${startFrom}` : ''}`;
+        const resp = await fetch(url, { method: 'POST' });
         const d = await resp.json();
+        const errHTML = d.errores?.length
+            ? `<ul class="mt-2 ml-4 list-disc text-xs space-y-0.5">${d.errores.map(e => `<li>${e}</li>`).join('')}</ul>`
+            : '';
         if (d.ok) {
             inner.innerHTML = `<div class="text-sm text-green-700 bg-green-50 border border-green-200 rounded-lg px-4 py-3">
                 <i class="fas fa-check-circle mr-1"></i>
-                <strong>${d.insertados.toLocaleString()}</strong> diagnósticos migrados en <strong>${d.lotes}</strong> lotes.
+                <strong>${d.insertados.toLocaleString()}</strong> / <strong>${d.total.toLocaleString()}</strong> diagnósticos migrados.
             </div>`;
         } else {
-            inner.innerHTML = `<div class="text-sm text-red-600 bg-red-50 border border-red-200 rounded-lg px-4 py-3">
-                <i class="fas fa-exclamation-circle mr-1"></i>${d.error || 'Error'}
-                ${d.errores?.length ? '<ul class="mt-1 ml-4 list-disc text-xs">' + d.errores.map(e => `<li>${e}</li>`).join('') + '</ul>' : ''}
+            const firstErr = d.errores?.[0] || '';
+            const resumeMatch = firstErr.match(/Lote (\d+)-/);
+            const resumeFrom = resumeMatch ? parseInt(resumeMatch[1]) : null;
+            inner.innerHTML = `<div class="text-sm text-orange-700 bg-orange-50 border border-orange-200 rounded-lg px-4 py-3">
+                <i class="fas fa-exclamation-triangle mr-1"></i>
+                <strong>${d.insertados.toLocaleString()}</strong> / <strong>${d.total.toLocaleString()}</strong> migrados — ${d.errores?.length || 0} lote(s) fallaron.
+                ${errHTML}
+                ${resumeFrom != null ? `<button onclick="ejecutarSyncDiag(${resumeFrom})" class="mt-3 flex items-center gap-1 bg-orange-500 hover:bg-orange-600 text-white text-xs font-medium px-3 py-1.5 rounded-lg">
+                    <i class="fas fa-play text-xs"></i> Reanudar desde #${resumeFrom.toLocaleString()}
+                </button>` : ''}
             </div>`;
         }
     } catch(e) {