diff --git a/src/app/api/portfolio/[portfolioId]/bulk-uploads/[uploadId]/onboard/route.ts b/src/app/api/portfolio/[portfolioId]/bulk-uploads/[uploadId]/start-address-matching/route.ts
similarity index 100%
rename from src/app/api/portfolio/[portfolioId]/bulk-uploads/[uploadId]/onboard/route.ts
rename to src/app/api/portfolio/[portfolioId]/bulk-uploads/[uploadId]/start-address-matching/route.ts
diff --git a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/OnboardingProgress.tsx b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/OnboardingProgress.tsx
index 91c81ef4..68160ebb 100644
--- a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/OnboardingProgress.tsx
+++ b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/OnboardingProgress.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useEffect, useState, useRef } from "react";
+import { useState, useSyncExternalStore } from "react";
 import { useRouter } from "next/navigation";
 import Link from "next/link";
 
@@ -26,10 +26,126 @@ interface Props {
   isDomnaUser: boolean;
 }
 
+interface Snapshot {
+  data: TaskData | null;
+  uploadStatus: UploadStatus | null;
+  fetchError: boolean;
+  finalizeError: string | null;
+}
+
 const TERMINAL_STATUSES = new Set(["complete", "completed", "failed", "failure", "error"]);
 const FAILED_STATUSES = new Set(["failed", "failure", "error"]);
 const FINAL_UPLOAD_STATUSES = new Set(["complete", "needs_review"]);
 
+function createProgressStore(args: {
+  taskId: string;
+  portfolioId: string;
+  uploadId: string;
+  onComplete: () => void;
+}) {
+  let snapshot: Snapshot = {
+    data: null,
+    uploadStatus: null,
+    fetchError: false,
+    finalizeError: null,
+  };
+  const listeners = new Set<() => void>();
+  let intervalId: ReturnType<typeof setInterval> | null = null;
+  let combineFired = false;
+  let finalizeFired = false;
+  let refreshed = false;
+
+  function emit(patch: Partial<Snapshot>) {
+    snapshot = { ...snapshot, ...patch };
+    listeners.forEach((l) => l());
+  }
+
+  async function fireFinalize() {
+    try {
+      const res = await fetch(
+        `/api/portfolio/${args.portfolioId}/bulk-uploads/${args.uploadId}/finalize`,
+        { method: "POST" }
+      );
+      if (!res.ok) {
+        const body = await res.json().catch(() => ({}));
+        const msg =
+          body?.detail || body?.error || `Finalize failed (${res.status})`;
+        emit({ finalizeError: msg });
+        finalizeFired = false;
+      }
+    } catch (err) {
+      console.error("Failed to trigger finalize:", err);
+      emit({ finalizeError: err instanceof Error ? err.message : "Network error" });
+      finalizeFired = false;
+    }
+  }
+
+  async function poll() {
+    try {
+      const res = await fetch(`/api/tasks/${args.taskId}/summary`);
+      if (!res.ok) { emit({ fetchError: true }); return; }
+      const json: TaskData = await res.json();
+      emit({ data: json });
+      const status = json.status.toLowerCase();
+
+      if (TERMINAL_STATUSES.has(status)) {
+        if (!FAILED_STATUSES.has(status) && !combineFired) {
+          combineFired = true;
+          fetch(`/api/portfolio/${args.portfolioId}/bulk-uploads/${args.uploadId}/combine`, {
+            method: "POST",
+          }).catch((err) => console.error("Failed to trigger combiner:", err));
+        }
+
+        const uploadRes = await fetch(
+          `/api/portfolio/${args.portfolioId}/bulk-uploads/${args.uploadId}`
+        );
+        if (uploadRes.ok) {
+          const upload: UploadStatus = await uploadRes.json();
+          emit({ uploadStatus: upload });
+
+          if (upload.status === "awaiting_review" && !finalizeFired) {
+            finalizeFired = true;
+            fireFinalize();
+          }
+
+          if (FINAL_UPLOAD_STATUSES.has(upload.status) && !refreshed) {
+            refreshed = true;
+            if (intervalId) clearInterval(intervalId);
+            intervalId = null;
+            args.onComplete();
+            return;
+          }
+        }
+      }
+    } catch {
+      emit({ fetchError: true });
+    }
+  }
+
+  return {
+    subscribe(listener: () => void) {
+      listeners.add(listener);
+      if (listeners.size === 1 && intervalId === null && !refreshed) {
+        poll();
+        intervalId = setInterval(poll, 3000);
+      }
+      return () => {
+        listeners.delete(listener);
+        if (listeners.size === 0 && intervalId !== null) {
+          clearInterval(intervalId);
+          intervalId = null;
+        }
+      };
+    },
+    getSnapshot: () => snapshot,
+    retryFinalize() {
+      emit({ finalizeError: null });
+      finalizeFired = true;
+      fireFinalize();
+    },
+  };
+}
+
 export default function OnboardingProgress({
   taskId,
   portfolioSlug,
@@ -38,88 +154,16 @@ export default function OnboardingProgress({
   isDomnaUser,
 }: Props) {
   const router = useRouter();
-  const [data, setData] = useState<TaskData | null>(null);
-  const [uploadStatus, setUploadStatus] = useState<UploadStatus | null>(null);
-  const [fetchError, setFetchError] = useState(false);
-  const [finalizeError, setFinalizeError] = useState<string | null>(null);
-  const intervalRef = useRef<ReturnType<typeof setInterval> | null>(null);
-  const combineFiredRef = useRef(false);
-  const finalizeFiredRef = useRef(false);
-  const refreshedRef = useRef(false);
-
-  async function fireFinalize() {
-    try {
-      const res = await fetch(
-        `/api/portfolio/${portfolioId}/bulk-uploads/${uploadId}/finalize`,
-        { method: "POST" }
-      );
-      if (!res.ok) {
-        const body = await res.json().catch(() => ({}));
-        const msg =
-          body?.detail || body?.error || `Finalize failed (${res.status})`;
-        setFinalizeError(msg);
-        finalizeFiredRef.current = false;
-      }
-    } catch (err) {
-      console.error("Failed to trigger finalize:", err);
-      setFinalizeError(err instanceof Error ? err.message : "Network error");
-      finalizeFiredRef.current = false;
-    }
-  }
-
-  function retryFinalize() {
-    setFinalizeError(null);
-    finalizeFiredRef.current = true;
-    fireFinalize();
-  }
-
-  useEffect(() => {
-    async function poll() {
-      try {
-        const res = await fetch(`/api/tasks/${taskId}/summary`);
-        if (!res.ok) { setFetchError(true); return; }
-        const json: TaskData = await res.json();
-        setData(json);
-        const status = json.status.toLowerCase();
-
-        if (TERMINAL_STATUSES.has(status)) {
-          if (!FAILED_STATUSES.has(status) && !combineFiredRef.current) {
-            combineFiredRef.current = true;
-            fetch(`/api/portfolio/${portfolioId}/bulk-uploads/${uploadId}/combine`, {
-              method: "POST",
-            }).catch((err) => console.error("Failed to trigger combiner:", err));
-          }
-
-          const uploadRes = await fetch(
-            `/api/portfolio/${portfolioId}/bulk-uploads/${uploadId}`
-          );
-          if (uploadRes.ok) {
-            const upload: UploadStatus = await uploadRes.json();
-            setUploadStatus(upload);
-
-            if (upload.status === "awaiting_review" && !finalizeFiredRef.current) {
-              finalizeFiredRef.current = true;
-              fireFinalize();
-            }
-
-            if (FINAL_UPLOAD_STATUSES.has(upload.status) && !refreshedRef.current) {
-              refreshedRef.current = true;
-              if (intervalRef.current) clearInterval(intervalRef.current);
-              router.refresh();
-              return;
-            }
-          }
-        }
-      } catch {
-        setFetchError(true);
-      }
-    }
-
-    poll();
-    intervalRef.current = setInterval(poll, 3000);
-    return () => { if (intervalRef.current) clearInterval(intervalRef.current); };
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [taskId, portfolioId, portfolioSlug, uploadId, router]);
+  const [store] = useState(() =>
+    createProgressStore({
+      taskId,
+      portfolioId,
+      uploadId,
+      onComplete: () => router.refresh(),
+    })
+  );
+  const snap = useSyncExternalStore(store.subscribe, store.getSnapshot, store.getSnapshot);
+  const { data, uploadStatus, fetchError, finalizeError } = snap;
 
   if (fetchError) return null;
   if (!data) {
@@ -191,7 +235,7 @@ export default function OnboardingProgress({
           </div>
           <button
             type="button"
-            onClick={retryFinalize}
+            onClick={() => store.retryFinalize()}
             className="shrink-0 px-2 py-1 rounded-md bg-red-600 text-white font-semibold hover:bg-red-700 transition-colors"
           >
             Retry
diff --git a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartOnboardingButton.tsx b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartAddressMatchingButton.tsx
similarity index 87%
rename from src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartOnboardingButton.tsx
rename to src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartAddressMatchingButton.tsx
index 60dad11f..ffe6c51c 100644
--- a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartOnboardingButton.tsx
+++ b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/StartAddressMatchingButton.tsx
@@ -10,7 +10,7 @@ interface Props {
   filename: string;
 }
 
-export default function StartOnboardingButton({ portfolioId, uploadId, filename }: Props) {
+export default function StartAddressMatchingButton({ portfolioId, uploadId, filename }: Props) {
   const router = useRouter();
   const [loading, setLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
@@ -39,8 +39,8 @@ export default function StartOnboardingButton({ portfolioId, uploadId, filename
 
       const { taskId, subTaskId } = await taskRes.json();
 
-      const onboardRes = await fetch(
-        `/api/portfolio/${portfolioId}/bulk-uploads/${uploadId}/onboard`,
+      const matchRes = await fetch(
+        `/api/portfolio/${portfolioId}/bulk-uploads/${uploadId}/start-address-matching`,
         {
           method: "POST",
           headers: { "Content-Type": "application/json" },
@@ -48,9 +48,9 @@ export default function StartOnboardingButton({ portfolioId, uploadId, filename
         }
       );
 
-      if (!onboardRes.ok) {
-        const data = await onboardRes.json().catch(() => ({}));
-        throw new Error(data.error ?? "Failed to start onboarding");
+      if (!matchRes.ok) {
+        const data = await matchRes.json().catch(() => ({}));
+        throw new Error(data.error ?? "Failed to start address matching");
       }
 
       router.refresh();
diff --git a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/page.tsx b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/page.tsx
index fb96eddc..d743097e 100644
--- a/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/page.tsx
+++ b/src/app/portfolio/[slug]/(portfolio)/bulk-upload/[uploadId]/page.tsx
@@ -15,7 +15,7 @@ import {
   ExclamationCircleIcon,
   ArrowPathIcon,
 } from "@heroicons/react/24/outline";
-import StartOnboardingButton from "./StartOnboardingButton";
+import StartAddressMatchingButton from "./StartAddressMatchingButton";
 import OnboardingProgress from "./OnboardingProgress";
 
 function formatDate(date: Date) {
@@ -166,7 +166,7 @@ export default async function BulkUploadDetailPage(props: {
                   Edit column mapping
                   <ArrowRightIcon className="h-3.5 w-3.5" />
                 </Link>
-                <StartOnboardingButton
+                <StartAddressMatchingButton
                   portfolioId={upload.portfolioId}
                   uploadId={uploadId}
                   filename={upload.filename}