diff --git a/api/migrate_email_bindings.php b/api/migrate_email_bindings.php
new file mode 100644
index 0000000..c5f3f50
--- /dev/null
+++ b/api/migrate_email_bindings.php
@@ -0,0 +1,87 @@
+<?php
+/**
+ * 第57批续17：一次性存量邮箱对账脚本
+ *
+ * 背景：邮箱权威权已交还 Java。新绑定走 PHP 投递队列 → Java 拉取写权威 db →
+ *       syncUserRegistrations 收敛 PHP 镜像。但存量 PHP users.email 里已绑定、
+ *       而 Java 权威 db 尚未对齐的邮箱，需要一次性对账兜底。
+ *
+ * 作用：遍历 users 表有 email 的记录，逐条 UPSERT 进 email_bind_return 队列
+ *       （幂等：先作废全部旧待处理行，再逐条重新投递），Java 端 pullEmailBindings
+ *       下一轮拉取即对齐。
+ *
+ * 安全：
+ *  - SECRET_KEY 认证（与 sync.php 同款）
+ *  - 幂等可重跑；只读 users.email（不写 users 表），Java 才是权威写
+ *
+ * 用法：curl ".../api/migrate_email_bindings.php?secret=<SECRET_KEY>"
+ * 返回：{"success":true,"count":<N>,"players":[...]}
+ */
+
+ob_start();
+
+// core.php 在 Web 根目录（与 sync.php 同款引入）
+$coreFile = __DIR__ . '/../core.php';
+if (!file_exists($coreFile)) {
+    while (ob_get_level() > 0) ob_end_clean();
+    header('Content-Type: application/json; charset=utf-8');
+    http_response_code(500);
+    echo json_encode(['success' => false, 'message' => 'core.php not found: ' . $coreFile], JSON_UNESCAPED_UNICODE);
+    exit;
+}
+require_once $coreFile;
+while (ob_get_level() > 0) ob_end_clean();
+ob_start();
+
+$secret = getParam('secret');
+if (!$secret || $secret !== SECRET_KEY) {
+    error('密钥验证失败', 403);
+}
+
+$db = getDB();
+
+// 兜底建表（与 pullEmailBindings 同款，防竞态）
+$db->exec("CREATE TABLE IF NOT EXISTS email_bind_return (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    player_name TEXT NOT NULL,
+    email TEXT NOT NULL,
+    source TEXT DEFAULT 'migrate',
+    pending INTEGER DEFAULT 1,
+    created_at INTEGER NOT NULL,
+    processed_at INTEGER DEFAULT 0
+)");
+
+$now = time();
+
+// 幂等：先作废全部旧待处理行（避免重跑堆积），再逐条重新投递
+$db->exec("UPDATE email_bind_return SET pending = 0 WHERE pending = 1");
+
+// 读存量 users.email（只读，不写 users 表）
+$stmt = $db->query("SELECT player_name, email FROM users WHERE email IS NOT NULL AND email != ''");
+
+$ins = $db->prepare("INSERT INTO email_bind_return (player_name, email, source, pending, created_at, processed_at)
+                     VALUES (:p, :e, 'migrate', 1, :t, 0)");
+
+$players = array();
+$count = 0;
+while ($row = $stmt->fetchArray(SQLITE3_ASSOC)) {
+    $pname = (string)$row['player_name'];
+    $email = (string)$row['email'];
+    if ($pname === '' || $email === '') continue;
+    $ins->reset();
+    $ins->bindValue(':p', $pname, SQLITE3_TEXT);
+    $ins->bindValue(':e', $email, SQLITE3_TEXT);
+    $ins->bindValue(':t', $now, SQLITE3_INTEGER);
+    $ins->execute();
+    $players[] = $pname;
+    $count++;
+}
+
+debugLog('[migrate_email_bindings] 存量邮箱对账已投递回推队列', [
+    'count' => $count,
+]);
+
+success([
+    'count' => $count,
+    'players' => $players,
+], '存量邮箱已投递回推队列，Java 下一轮拉取即对齐权威 db');
diff --git a/api/sync.php b/api/sync.php
index 66f7d89..d74ac1d 100644
--- a/api/sync.php
+++ b/api/sync.php
@@ -306,6 +306,9 @@ switch ($action) {
     case 'check_pending_web_email_bind_requests':
         checkPendingWebEmailBindRequests();
         break;
+    case 'pull_email_bindings':
+        pullEmailBindings();
+        break;
     case 'web_email_bind_result':
         webEmailBindResult();
         break;
@@ -4383,16 +4386,33 @@ function maskEmail($email) {
 // ===== 第57批续7：Java端密码验证通过后直接完成邮箱绑定 =====
 function acctCompleteEmailBind($requestId, $player, $email) {
     $db = getDB();
-    $upd = $db->prepare("UPDATE users SET email = :e WHERE player_name = :p");
-    $upd->bindValue(':e', $email, SQLITE3_TEXT);
-    $upd->bindValue(':p', $player, SQLITE3_TEXT);
-    $upd->execute();
-    if ($db->changes() <= 0) return false;
+    // ★ 第57批续17：权威权交还 Java——PHP 不再独占写 users.email（避免与 Java db 双写冲突）。
+    //   改为把 (player,email,来源=网页绑定验证通过) 投递到 email_bind_return 队列，
+    //   Java 定时 pull_email_bindings 拉取后写权威 db，再经 sync_players 收敛 PHP 镜像。
+    $db->exec("CREATE TABLE IF NOT EXISTS email_bind_return (
+        id INTEGER PRIMARY KEY AUTOINCREMENT,
+        player_name TEXT NOT NULL,
+        email TEXT NOT NULL,
+        source TEXT DEFAULT 'web_bind',
+        pending INTEGER DEFAULT 1,
+        created_at INTEGER NOT NULL,
+        processed_at INTEGER DEFAULT 0
+    )");
+    // 同玩家保留最新一条待处理（幂等：旧未处理作废，避免拉取到过期值）
+    $void = $db->prepare("UPDATE email_bind_return SET pending = 0 WHERE player_name = :p AND pending = 1");
+    $void->bindValue(':p', $player, SQLITE3_TEXT);
+    $void->execute();
+    $ins = $db->prepare("INSERT INTO email_bind_return (player_name, email, source, pending, created_at, processed_at) VALUES (:p, :e, 'web_bind', 1, :t, 0)");
+    $ins->bindValue(':p', $player, SQLITE3_TEXT);
+    $ins->bindValue(':e', $email, SQLITE3_TEXT);
+    $ins->bindValue(':t', time(), SQLITE3_INTEGER);
+    $ins->execute();
+    // 网页绑定请求本身标记完成（这是前端流程的终态，与邮箱是否入 PHP 解耦）
     $done = $db->prepare("UPDATE web_email_bind_requests SET status = 'completed', processed_at = :t WHERE id = :id");
     $done->bindValue(':t', time(), SQLITE3_INTEGER);
     $done->bindValue(':id', (int)$requestId, SQLITE3_INTEGER);
     $done->execute();
-    debugLog('[sync.php] Java端验证通过，直接完成邮箱绑定', ['player' => $player, 'id' => $requestId]);
+    debugLog('[sync.php] 邮箱绑定验证通过，已投递回推队列待Java确认（不直接写users.email）', ['player' => $player, 'id' => $requestId, 'email' => $email]);
     return true;
 }
 
@@ -5203,6 +5223,44 @@ function webEmailBindResult() {
     success(['request_id' => (int)$requestId, 'status' => $newStatus]);
 }
 
+// ===== 第57批续17：Java 定时拉取待确认的邮箱变更（PHP 不独占写 users.email，权威权交还 Java）=====
+// PHP 只负责验证+投递队列；Java 拉走后写权威 db，再经 sync_players 收敛 PHP 镜像。
+function pullEmailBindings() {
+    $secret = getParam('secret');
+    if (!$secret || $secret !== SECRET_KEY) error('密钥验证失败', 403);
+    $db = getDB();
+    $db->exec("CREATE TABLE IF NOT EXISTS email_bind_return (
+        id INTEGER PRIMARY KEY AUTOINCREMENT,
+        player_name TEXT NOT NULL,
+        email TEXT NOT NULL,
+        source TEXT DEFAULT 'web_bind',
+        pending INTEGER DEFAULT 1,
+        created_at INTEGER NOT NULL,
+        processed_at INTEGER DEFAULT 0
+    )");
+    // 拉取全部待确认（pending=1），逐条返回给 Java
+    $stmt = $db->prepare("SELECT id, player_name, email, source FROM email_bind_return WHERE pending = 1 ORDER BY id ASC");
+    $result = $stmt->execute();
+    $rows = array();
+    $ids = array();
+    while ($row = $result->fetchArray(SQLITE3_ASSOC)) {
+        $rows[] = array(
+            'id' => (int)$row['id'],
+            'player_name' => (string)$row['player_name'],
+            'email' => (string)$row['email'],
+            'source' => (string)$row['source]
+        );
+        $ids[] = (int)$row['id'];
+    }
+    // 拉取即标记 pending=0（Java 收到后会写权威 db；若 Java 宕机下轮不再拉到——
+    // 与既有 check_pending 拉取即标记语义一致；存量对账用 migrate 重新投递兜底）
+    if (!empty($ids)) {
+        $idList = implode(',', $ids);
+        $db->exec("UPDATE email_bind_return SET pending = 0, processed_at = " . time() . " WHERE id IN ($idList) AND pending = 1");
+    }
+    success(['bindings' => $rows, 'count' => count($rows)]);
+}
+
 // ===== CDK验证（供sdf1插件调用）=====
 // sdf1插件本地CDK未找到时，请求Web后端验证
 function validateCdk() {