diff --git a/.github/extensions/external-plugin-review-board/extension.mjs b/.github/extensions/external-plugin-review-board/extension.mjs
index b28cc4da4..68ce27a69 100644
--- a/.github/extensions/external-plugin-review-board/extension.mjs
+++ b/.github/extensions/external-plugin-review-board/extension.mjs
@@ -70,7 +70,7 @@ async function getIssue(number, { force = false } = {}) {
 
 async function startReview({ numbers, instanceId, send }) {
     const items = store.pendingReview(numbers);
-    if (!items.length) return { queued: [], message: "Nothing to review — all items already have an AI review." };
+    if (!items.length) return { queued: [], message: "Nothing to review — no eligible unreviewed items remain." };
     const queued = items.map((item) => item.number);
     const snapshots = await store.markQueued(queued);
     const prompt = buildReviewPrompt({
diff --git a/.github/extensions/external-plugin-review-board/lib/state.mjs b/.github/extensions/external-plugin-review-board/lib/state.mjs
index f42a99521..d75de61d1 100644
--- a/.github/extensions/external-plugin-review-board/lib/state.mjs
+++ b/.github/extensions/external-plugin-review-board/lib/state.mjs
@@ -136,7 +136,8 @@ export class BoardStore {
     }
 
     pendingReview(numbers) {
-        const all = Object.values(this.state.items).filter((item) => !item.decision && item.reviewStatus !== "queued");
+        const all = Object.values(this.state.items).filter((item) =>
+            !item.decision && !item.pendingDecision && item.reviewStatus !== "queued");
         if (numbers?.length) {
             const wanted = new Set(numbers.map(Number));
             return all.filter((item) => wanted.has(item.number));
diff --git a/.github/extensions/external-plugin-review-board/public/app.js b/.github/extensions/external-plugin-review-board/public/app.js
index 797c5fe96..d06bfc8fa 100644
--- a/.github/extensions/external-plugin-review-board/public/app.js
+++ b/.github/extensions/external-plugin-review-board/public/app.js
@@ -561,6 +561,11 @@ function resetConfirm() {
     ui.approve.disabled = false;
     ui.reject.disabled = false;
     updatePreview();
+    const item = findItem(selected);
+    if (bulkBusy || item?.pendingDecision) {
+        ui.approve.disabled = true;
+        ui.reject.disabled = true;
+    }
 }
 
 async function decide(kind) {
diff --git a/eng/external-plugin-review-board.test.mjs b/eng/external-plugin-review-board.test.mjs
new file mode 100644
index 000000000..e0f5a8222
--- /dev/null
+++ b/eng/external-plugin-review-board.test.mjs
@@ -0,0 +1,50 @@
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import vm from "node:vm";
+import { test } from "node:test";
+import { BoardStore } from "../.github/extensions/external-plugin-review-board/lib/state.mjs";
+
+test("external-plugin-review-board excludes items with pending decisions from AI review", () => {
+    const store = new BoardStore("unused", "github/awesome-copilot");
+    store.state.items = {
+        "1": { number: 1, reviewStatus: "unreviewed" },
+        "2": { number: 2, reviewStatus: "unreviewed", pendingDecision: { kind: "approve" } },
+        "3": { number: 3, reviewStatus: "queued" },
+        "4": { number: 4, reviewStatus: "unreviewed", decision: { kind: "reject" } },
+    };
+
+    assert.deepEqual(store.pendingReview().map(({ number }) => number), [1]);
+    assert.deepEqual(store.pendingReview([1, 2, 3, 4]).map(({ number }) => number), [1]);
+});
+
+test("resetConfirm keeps decision buttons disabled while a decision is pending", async () => {
+    const source = await readFile(
+        new URL("../.github/extensions/external-plugin-review-board/public/app.js", import.meta.url),
+        "utf8",
+    );
+    const start = source.indexOf("function resetConfirm()");
+    const end = source.indexOf("async function decide(", start);
+    assert.notEqual(start, -1);
+    assert.notEqual(end, -1);
+
+    const button = () => ({
+        disabled: false,
+        textContent: "",
+        classList: { remove() {} },
+    });
+    const context = vm.createContext({
+        clearTimeout() {},
+        pendingConfirm: { timer: null, kind: "approve" },
+        ui: { approve: button(), reject: button() },
+        bulkBusy: false,
+        selected: 42,
+        findItem: () => ({ pendingDecision: { kind: "approve" } }),
+        updatePreview() {},
+    });
+    vm.runInContext(source.slice(start, end), context);
+
+    context.resetConfirm();
+
+    assert.equal(context.ui.approve.disabled, true);
+    assert.equal(context.ui.reject.disabled, true);
+});
diff --git a/eng/open-pr-board.test.mjs b/eng/open-pr-board.test.mjs
index b6d5e4f8e..151b3ec50 100644
--- a/eng/open-pr-board.test.mjs
+++ b/eng/open-pr-board.test.mjs
@@ -6,7 +6,7 @@ import vm from "node:vm";
 import { test } from "node:test";
 import { BoardStore } from "../.github/extensions/open-pr-board/lib/state.mjs";
 import { applyDecisionOnGitHub } from "../.github/extensions/open-pr-board/lib/decisions.mjs";
-import { approveAndEnableAutoMerge } from "../.github/extensions/open-pr-board/lib/github.mjs";
+import { approveAndEnableAutoMerge, listOpenPullRequests } from "../.github/extensions/open-pr-board/lib/github.mjs";
 import { REVIEW_FIELDS_SCHEMA } from "../.github/extensions/open-pr-board/lib/review-prompt.mjs";
 
 const pr = (headRefOid = "first") => ({
@@ -59,6 +59,50 @@ test("approval and auto-merge are pinned to the reviewed commit", async () => {
   assert.deepEqual(calls[2].args, ["pr", "merge", "1", "-R", "example/repo", "--auto", "--merge", "--match-head-commit", headRefOid]);
 });
 
+test("open pull requests fetch checks with bounded concurrency, preserve order, and tolerate a failed check request", async () => {
+  const numbers = [41, 7, 23, 4, 99, 12, 68, 51];
+  let active = 0;
+  let peak = 0;
+  const requested = [];
+  const runner = async (args) => {
+    if (args[1] === "list") {
+      return JSON.stringify(numbers.map((number) => ({ number, title: `PR ${number}`, labels: [] })));
+    }
+    if (args[1] === "view") {
+      const number = Number(args[2]);
+      requested.push(number);
+      active++;
+      peak = Math.max(peak, active);
+      try {
+        await new Promise((resolve) => setTimeout(resolve, 10));
+        if (number === 23) throw new Error("check request failed");
+        return JSON.stringify({
+          statusCheckRollup: [{ name: `check-${number}`, status: "COMPLETED", conclusion: "SUCCESS" }],
+        });
+      } finally {
+        active--;
+      }
+    }
+    throw new Error(`Unexpected gh command: ${args.join(" ")}`);
+  };
+
+  const pullRequests = await listOpenPullRequests("example/repo", runner);
+
+  assert.ok(peak <= 6, "check requests should not exceed the six-request limit");
+  assert.ok(peak > 1, "check requests should run concurrently");
+  assert.deepEqual(pullRequests.map(({ number }) => number), numbers, "results should preserve list order");
+  assert.deepEqual(requested.sort((a, b) => a - b), [...numbers].sort((a, b) => a - b), "every PR should request checks");
+  for (const pullRequest of pullRequests) {
+    if (pullRequest.number === 23) {
+      assert.deepEqual(pullRequest.checks, []);
+      assert.equal(pullRequest.checksState, "none");
+    } else {
+      assert.deepEqual(pullRequest.checks.map(({ name }) => name), [`check-${pullRequest.number}`]);
+      assert.equal(pullRequest.checksState, "success");
+    }
+  }
+});
+
 test("approval refuses a missing SHA, changed head, or closed pull request without writing", async () => {
   let calls = 0;
   const runner = async () => { calls++; throw new Error("must not run"); };