diff --git a/.github/workflows/ios-xcode-cloud.yml b/.github/workflows/ios-xcode-cloud.yml
index 75edea76..64ee9dd1 100644
--- a/.github/workflows/ios-xcode-cloud.yml
+++ b/.github/workflows/ios-xcode-cloud.yml
@@ -13,6 +13,7 @@ on:
           - monitor
           - describe
           - store-status
+          - cancel-review
         default: inspect
       workflow_id:
         description: Optional Xcode Cloud workflow ID; auto-selects a single enabled Archive workflow when empty
@@ -30,6 +31,10 @@ on:
         description: App Store Connect build resource ID to inspect
         required: false
         type: string
+      current_review_build_id:
+        description: Exact linked build ID expected before canceling a mismatched review
+        required: false
+        type: string
 
 permissions:
   contents: read
@@ -57,6 +62,7 @@ jobs:
           XCODE_CLOUD_BUILD_RUN_ID: ${{ inputs.build_run_id }}
           APP_STORE_VERSION: ${{ inputs.app_store_version }}
           APP_STORE_BUILD_ID: ${{ inputs.app_store_build_id }}
+          CURRENT_REVIEW_BUILD_ID: ${{ inputs.current_review_build_id }}
         run: |
           case "$XCODE_CLOUD_MODE" in
             inspect)
@@ -95,6 +101,16 @@ jobs:
                 --version "$APP_STORE_VERSION" \
                 --build-id "$APP_STORE_BUILD_ID"
               ;;
+            cancel-review)
+              if [[ -z "$APP_STORE_VERSION" || -z "$APP_STORE_BUILD_ID" || -z "$CURRENT_REVIEW_BUILD_ID" ]]; then
+                echo "::error::app_store_version, app_store_build_id, and current_review_build_id are required in cancel-review mode"
+                exit 1
+              fi
+              python3 scripts/xcode-cloud-control.py cancel-review \
+                --version "$APP_STORE_VERSION" \
+                --current-build-id "$CURRENT_REVIEW_BUILD_ID" \
+                --replacement-build-id "$APP_STORE_BUILD_ID"
+              ;;
             *)
               echo "::error::Unsupported Xcode Cloud mode: $XCODE_CLOUD_MODE"
               exit 1
diff --git a/scripts/xcode-cloud-control.py b/scripts/xcode-cloud-control.py
index 98d1fbd2..21c7233f 100644
--- a/scripts/xcode-cloud-control.py
+++ b/scripts/xcode-cloud-control.py
@@ -547,6 +547,71 @@ def command_store_status(args: argparse.Namespace, client: AppStoreConnect) -> N
         )
 
 
+def command_cancel_review(args: argparse.Namespace, client: AppStoreConnect) -> None:
+    version_query = urllib.parse.urlencode(
+        {
+            "filter[platform]": "IOS",
+            "filter[versionString]": args.version,
+            "fields[appStoreVersions]": "versionString,appStoreState,build",
+            "include": "build",
+            "limit": 10,
+        }
+    )
+    versions = client.request("GET", f"/v1/apps/{client.app_id}/appStoreVersions?{version_query}").get("data") or []
+    if len(versions) != 1:
+        raise SystemExit(f"Expected exactly one iOS App Store version {args.version}; found {len(versions)}")
+    version = versions[0]
+    attributes = version.get("attributes") or {}
+    linked_build = ((version.get("relationships") or {}).get("build") or {}).get("data") or {}
+    if attributes.get("appStoreState") != "WAITING_FOR_REVIEW" or linked_build.get("id") != args.current_build_id:
+        raise SystemExit("App Store version state or linked build changed; refusing to cancel review")
+
+    replacement = client.request(
+        "GET", f"/v1/builds/{args.replacement_build_id}?fields[builds]=version,processingState"
+    ).get("data") or {}
+    prerelease = client.request(
+        "GET", f"/v1/builds/{args.replacement_build_id}/preReleaseVersion"
+    ).get("data") or {}
+    if (
+        (replacement.get("attributes") or {}).get("processingState") != "VALID"
+        or (prerelease.get("attributes") or {}).get("version") != args.version
+    ):
+        raise SystemExit("Replacement build is not VALID for the requested marketing version")
+
+    review_query = urllib.parse.urlencode(
+        {
+            "filter[platform]": "IOS",
+            "filter[state]": "WAITING_FOR_REVIEW",
+            "fields[reviewSubmissions]": "state,appStoreVersionForReview",
+            "include": "appStoreVersionForReview",
+            "limit": 50,
+        }
+    )
+    submissions = client.request("GET", f"/v1/apps/{client.app_id}/reviewSubmissions?{review_query}").get("data") or []
+    matching = [
+        submission for submission in submissions
+        if (((submission.get("relationships") or {}).get("appStoreVersionForReview") or {}).get("data") or {}).get("id") == version.get("id")
+    ]
+    if len(matching) != 1:
+        raise SystemExit(f"Expected one waiting review submission for {args.version}; found {len(matching)}")
+    submission_id = matching[0]["id"]
+    items = client.request("GET", f"/v1/reviewSubmissions/{submission_id}/items?limit=50").get("data") or []
+    if len(items) != 1 or (
+        (((items[0].get("relationships") or {}).get("appStoreVersion") or {}).get("data") or {}).get("id") != version.get("id")
+    ):
+        raise SystemExit("Review submission contains other items; refusing to cancel it")
+
+    response = client.request(
+        "PATCH",
+        f"/v1/reviewSubmissions/{submission_id}",
+        {"data": {"type": "reviewSubmissions", "id": submission_id, "attributes": {"canceled": True}}},
+    )
+    print(
+        f"Canceled review submission {submission_id} for {args.version}; "
+        f"state={((response.get('data') or {}).get('attributes') or {}).get('state')}"
+    )
+
+
 def build_parser() -> argparse.ArgumentParser:
     parser = argparse.ArgumentParser(description=__doc__)
     sub = parser.add_subparsers(dest="command", required=True)
@@ -575,6 +640,11 @@ def build_parser() -> argparse.ArgumentParser:
     status = sub.add_parser("store-status", help="Inspect an App Store version/build")
     status.add_argument("--version", required=True)
     status.add_argument("--build-id", required=True)
+
+    cancel = sub.add_parser("cancel-review", help="Cancel a mismatched iOS review submission")
+    cancel.add_argument("--version", required=True)
+    cancel.add_argument("--current-build-id", required=True)
+    cancel.add_argument("--replacement-build-id", required=True)
     return parser
 
 
@@ -596,6 +666,9 @@ def main(argv: list[str] | None = None) -> None:
     if args.command == "store-status":
         command_store_status(args, client)
         return
+    if args.command == "cancel-review":
+        command_cancel_review(args, client)
+        return
     raise SystemExit(f"Unsupported command: {args.command}")
 
 
diff --git a/scripts/xcode-cloud-control.test.mjs b/scripts/xcode-cloud-control.test.mjs
index 2eb93313..267a98e5 100644
--- a/scripts/xcode-cloud-control.test.mjs
+++ b/scripts/xcode-cloud-control.test.mjs
@@ -1,5 +1,6 @@
 import { describe, expect, test } from "bun:test";
 import { readFileSync } from "node:fs";
+import { spawnSync } from "node:child_process";
 
 describe("Xcode Cloud control", () => {
   test("exposes start, wait, and VALID-build resolution for store delivery", () => {
@@ -62,4 +63,49 @@ describe("Xcode Cloud control", () => {
     expect(pbxproj).not.toContain("MARKETING_VERSION = 1.74.0;");
     expect(pbxproj).toContain(`MARKETING_VERSION = ${marketing};`);
   });
+
+  test("cancels only the matching single-item review with a valid replacement build", () => {
+    const program = `
+import argparse, importlib.util
+spec = importlib.util.spec_from_file_location("cloud", "scripts/xcode-cloud-control.py")
+cloud = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(cloud)
+class Client:
+    app_id = "app"
+    def __init__(self, linked="old", items=1):
+        self.linked, self.items, self.patches = linked, items, []
+    def request(self, method, path, body=None):
+        if method == "PATCH":
+            self.patches.append((path, body))
+            return {"data": {"attributes": {"state": "CANCELING"}}}
+        if "/appStoreVersions?" in path:
+            return {"data": [{"id": "version", "attributes": {"appStoreState": "WAITING_FOR_REVIEW"},
+                "relationships": {"build": {"data": {"id": self.linked}}}}]}
+        if "/builds/new?" in path:
+            return {"data": {"attributes": {"processingState": "VALID"}}}
+        if "/builds/new/preReleaseVersion" in path:
+            return {"data": {"attributes": {"version": "1.98.0"}}}
+        if "/reviewSubmissions?" in path:
+            return {"data": [{"id": "submission", "relationships": {
+                "appStoreVersionForReview": {"data": {"id": "version"}}}}]}
+        if "/reviewSubmissions/submission/items" in path:
+            return {"data": [{"relationships": {"appStoreVersion": {"data": {"id": "version"}}}}] * self.items}
+        raise AssertionError(path)
+args = argparse.Namespace(version="1.98.0", current_build_id="old", replacement_build_id="new")
+good = Client()
+cloud.command_cancel_review(args, good)
+assert len(good.patches) == 1
+assert good.patches[0][1]["data"]["attributes"] == {"canceled": True}
+for unsafe in (Client(linked="changed"), Client(items=2)):
+    try:
+        cloud.command_cancel_review(args, unsafe)
+    except SystemExit:
+        pass
+    else:
+        raise AssertionError("Unsafe review was not rejected")
+    assert unsafe.patches == []
+`;
+    const result = spawnSync("python3", ["-c", program], { encoding: "utf8" });
+    expect(result.status).toBe(0);
+  });
 });