diff --git a/.github/workflows/locize-i18n-sync.yml b/.github/workflows/locize-i18n-sync.yml
index c820b52797..5fb3fcdc7e 100644
--- a/.github/workflows/locize-i18n-sync.yml
+++ b/.github/workflows/locize-i18n-sync.yml
@@ -2,11 +2,12 @@ name: Sync Locize Translations & Create Translation PR
 
 on:
   push:
-    branches: [main]
+    branches: [dev]
     paths:
       - 'client/src/locales/en/**'
   repository_dispatch:
     types: [locize/versionPublished]
+  workflow_dispatch:
 
 concurrency:
   group: locize-i18n-sync
@@ -51,7 +52,7 @@ jobs:
 
   create-pull-request:
     name: Create Translation PR on Version Published
-    if: ${{ github.event_name == 'repository_dispatch' }}
+    if: ${{ github.event_name == 'repository_dispatch' || github.event_name == 'workflow_dispatch' }}
     runs-on: ubuntu-latest
     needs: sync-translations
     permissions:
@@ -61,6 +62,7 @@ jobs:
       - name: Checkout Repository
         uses: actions/checkout@v5
         with:
+          ref: dev
           persist-credentials: false
 
       # Keep a baseline so generated changes can be checked before opening a PR.
@@ -75,6 +77,12 @@ jobs:
           path: "client/src/locales"
           version: latest
 
+      - name: Preserve Repository Translations Missing from locize
+        run: |
+          node scripts/merge-locize-download.mjs \
+            --base-dir "$RUNNER_TEMP/locize-locale-baseline" \
+            --current-dir client/src/locales
+
       - name: Validate Downloaded Translations
         run: |
           node scripts/validate-locize-download.mjs \
@@ -91,7 +99,7 @@ jobs:
           add-paths: |
             client/src/locales/**
           commit-message: "🌍 i18n: Update translation.json with latest translations"
-          base: main
+          base: dev
           branch: i18n/locize-translation-update
           title: "🌍 i18n: Update translation.json with latest translations"
           body: |
diff --git a/scripts/merge-locize-download.mjs b/scripts/merge-locize-download.mjs
new file mode 100644
index 0000000000..b798f915aa
--- /dev/null
+++ b/scripts/merge-locize-download.mjs
@@ -0,0 +1,89 @@
+#!/usr/bin/env node
+
+import { mkdir, readdir, readFile, writeFile } from 'node:fs/promises';
+import path from 'node:path';
+
+const args = new Map();
+for (let index = 2; index < process.argv.length; index += 1) {
+  if (!process.argv[index].startsWith('--')) continue;
+  args.set(process.argv[index].slice(2), process.argv[index + 1]);
+  index += 1;
+}
+
+const baseDir = args.get('base-dir');
+const currentDir = args.get('current-dir');
+if (!baseDir || !currentDir) {
+  console.error('Usage: merge-locize-download.mjs --base-dir <path> --current-dir <path>');
+  process.exit(2);
+}
+
+function isObject(value) {
+  return value !== null && typeof value === 'object' && !Array.isArray(value);
+}
+
+function leafCount(value) {
+  if (!isObject(value)) return 1;
+  return Object.values(value).reduce((count, child) => count + leafCount(child), 0);
+}
+
+function mergeValues(base, current) {
+  if (!isObject(base) || !isObject(current)) return { value: current, restored: 0 };
+
+  let restored = 0;
+  const value = {};
+  for (const [key, baseValue] of Object.entries(base)) {
+    if (!Object.hasOwn(current, key)) {
+      value[key] = baseValue;
+      restored += leafCount(baseValue);
+      continue;
+    }
+    const merged = mergeValues(baseValue, current[key]);
+    value[key] = merged.value;
+    restored += merged.restored;
+  }
+
+  for (const [key, currentValue] of Object.entries(current)) {
+    if (!Object.hasOwn(base, key)) value[key] = currentValue;
+  }
+
+  return { value, restored };
+}
+
+async function jsonFiles(directory, relative = '') {
+  const entries = await readdir(path.join(directory, relative), { withFileTypes: true });
+  const files = [];
+  for (const entry of entries) {
+    const entryRelative = path.join(relative, entry.name);
+    if (entry.isDirectory()) files.push(...(await jsonFiles(directory, entryRelative)));
+    else if (entry.isFile() && entry.name.endsWith('.json')) files.push(entryRelative);
+  }
+  return files;
+}
+
+async function readJson(filePath) {
+  return JSON.parse(await readFile(filePath, 'utf8'));
+}
+
+let restored = 0;
+let changedFiles = 0;
+for (const relative of await jsonFiles(baseDir)) {
+  const basePath = path.join(baseDir, relative);
+  const currentPath = path.join(currentDir, relative);
+  const base = await readJson(basePath);
+  let current;
+  try {
+    current = await readJson(currentPath);
+  } catch (error) {
+    if (error.code !== 'ENOENT') throw error;
+    current = {};
+  }
+
+  const merged = mergeValues(base, current);
+  if (merged.restored === 0) continue;
+  await mkdir(path.dirname(currentPath), { recursive: true });
+  await writeFile(currentPath, `${JSON.stringify(merged.value, null, 2)}\n`);
+  restored += merged.restored;
+  changedFiles += 1;
+}
+
+console.log(`Preserved ${restored} repository translation value(s) across ${changedFiles} file(s).`);