diff --git a/src/class-job-payload.php b/src/class-job-payload.php
index 08fcbb1..e02efe4 100644
--- a/src/class-job-payload.php
+++ b/src/class-job-payload.php
@@ -174,8 +174,8 @@ private static function current_site_id(): int
      * During a full-network scan, get_site_url() can be filtered to a mapped,
      * stale, or secondary-network domain. Bootstrapping a fresh executor with
      * that URL can select a different routed database before switch_to_blog()
-     * runs. The wp_blogs domain and path are authoritative for switched-site
-     * scans because WordPress resolves them to the same blog the scanner read.
+     * runs. Prefer a uniquely owned active domain mapping. Fall back to the
+     * wp_blogs domain only when another blog has not claimed it.
      */
     private static function current_site_url(): string
     {
@@ -202,6 +202,80 @@ private static function current_site_url(): string
             $path = '/' . $path;
         }
 
+        $site_id = get_current_blog_id();
+        $mapped_url = self::current_mapped_site_url($site_id, $path, $scheme === 'https');
+        if ($mapped_url !== '') {
+            return $mapped_url;
+        }
+
+        if (self::canonical_domain_is_mapped_elsewhere((string) $site->domain, $site_id)) {
+            return '';
+        }
+
         return $scheme . '://' . (string) $site->domain . $path;
     }
+
+    /**
+     * Return a uniquely owned active mapping for a switched blog.
+     */
+    private static function current_mapped_site_url(int $site_id, string $path, bool $secure): string
+    {
+        global $wpdb;
+
+        $table = $wpdb->base_prefix . 'wu_domain_mappings';
+        if (!preg_match('/^[A-Za-z0-9_]+$/', $table)) {
+            return '';
+        }
+
+        $found = $wpdb->get_var($wpdb->prepare('SHOW TABLES LIKE %s', $wpdb->esc_like($table)));
+        if ($found !== $table) {
+            return '';
+        }
+
+        $sql = 'SELECT candidate.domain, candidate.secure FROM `' . $table . '` candidate '
+            . 'WHERE candidate.blog_id = %d AND candidate.active = 1 '
+            . 'AND NOT EXISTS (SELECT 1 FROM `' . $table . '` conflict '
+            . 'WHERE conflict.domain = candidate.domain AND conflict.active = 1 '
+            . 'AND conflict.blog_id <> candidate.blog_id) '
+            . 'ORDER BY candidate.primary_domain DESC, candidate.id DESC LIMIT 1';
+        $mapping = $wpdb->get_row($wpdb->prepare($sql, $site_id));
+        if (!is_object($mapping) || empty($mapping->domain)) {
+            return '';
+        }
+
+        $domain = strtolower(rtrim(trim((string) $mapping->domain), '.'));
+        if (preg_match('/^[a-z0-9.-]+(?::[0-9]+)?$/', $domain) !== 1) {
+            return '';
+        }
+
+        return (!empty($mapping->secure) || $secure ? 'https://' : 'http://') . $domain . $path;
+    }
+
+    /**
+     * Check whether a canonical domain is actively mapped to another blog.
+     */
+    private static function canonical_domain_is_mapped_elsewhere(string $domain, int $site_id): bool
+    {
+        global $wpdb;
+
+        $table = $wpdb->base_prefix . 'wu_domain_mappings';
+        if (!preg_match('/^[A-Za-z0-9_]+$/', $table)) {
+            return false;
+        }
+
+        $found = $wpdb->get_var($wpdb->prepare('SHOW TABLES LIKE %s', $wpdb->esc_like($table)));
+        if ($found !== $table) {
+            return false;
+        }
+
+        $sql = 'SELECT COUNT(*) FROM `' . $table . '` '
+            . 'WHERE domain = %s AND active = 1 AND blog_id <> %d';
+        $conflicts = $wpdb->get_var($wpdb->prepare(
+            $sql,
+            strtolower(rtrim(trim($domain), '.')),
+            $site_id
+        ));
+
+        return (int) $conflicts > 0;
+    }
 }
diff --git a/src/class-worker-process.php b/src/class-worker-process.php
index 2565f7c..75c33bb 100644
--- a/src/class-worker-process.php
+++ b/src/class-worker-process.php
@@ -66,6 +66,8 @@ class Worker_Process
     private int $last_rescan_duration = 0;
     private bool $is_ready = false;
     private string $failure_reason = '';
+    /** @var array<int, true> */
+    private array $unroutable_sites_logged = [];
 
     public function __construct(string $wp_load, string $primary_domain, string $execute_script, string $scan_script = '')
     {
@@ -242,6 +244,17 @@ private function mark_unready(int $worker_id, string $context, \Throwable $e): v
      */
     private function schedule_timer(Job_Payload $payload): void
     {
+        if ($payload->site_url === '') {
+            if (!isset($this->unroutable_sites_logged[$payload->site_id])) {
+                Worker::log(sprintf(
+                    '[SKIP][UNROUTABLE] Site %d has no uniquely owned bootstrap domain; jobs remain pending until routing metadata is repaired.',
+                    $payload->site_id
+                ));
+                $this->unroutable_sites_logged[$payload->site_id] = true;
+            }
+            return;
+        }
+
         $key = $payload->tracking_key();
         if (isset($this->pending_timers[$key])) {
             return;
diff --git a/tests/regression.php b/tests/regression.php
index 4b5a01e..6dd1f77 100644
--- a/tests/regression.php
+++ b/tests/regression.php
@@ -127,6 +127,9 @@ public function get_error_message(): string
     $GLOBALS['test_site_url'] = 'https://example.test';
     $GLOBALS['test_site_domain'] = 'example.test';
     $GLOBALS['test_site_path'] = '/';
+    $GLOBALS['test_mapping_table_exists'] = false;
+    $GLOBALS['test_mapping_row'] = null;
+    $GLOBALS['test_canonical_mapping_conflicts'] = 0;
 
     $worker_entrypoint = file_get_contents(__DIR__ . '/../bin/worker.php');
     assert_true(is_string($worker_entrypoint), 'Worker entrypoint must be readable');
@@ -158,9 +161,21 @@ public function esc_like(string $text): string
 
         public function get_var(string $query): ?string
         {
+            if (str_contains($query, 'SHOW TABLES LIKE') && str_contains($query, 'wu_domain_mappings')) {
+                return $GLOBALS['test_mapping_table_exists'] ? 'wp_wu_domain_mappings' : null;
+            }
+            if (str_contains($query, 'COUNT(*)') && str_contains($query, 'wu_domain_mappings')) {
+                return (string) $GLOBALS['test_canonical_mapping_conflicts'];
+            }
             return null;
         }
 
+        public function get_row(string $query): ?object
+        {
+            unset($query);
+            return $GLOBALS['test_mapping_row'];
+        }
+
         public function query(string $query)
         {
             $this->queries[] = $query;
@@ -541,6 +556,39 @@ function invoke_private(object $object, string $method, array $args = [])
         $switched_cron_payload->site_url,
         'WP-Cron factory payloads must preserve the canonical switched-site bootstrap URL'
     );
+    $GLOBALS['test_mapping_table_exists'] = true;
+    $GLOBALS['test_mapping_row'] = (object) [
+        'domain' => 'translate.example.test',
+        'secure' => '1',
+    ];
+    $mapped_payload = new Job_Payload([
+        'hook' => 'mapped_site_hook',
+        'timestamp' => 1710000000,
+        'source' => 'action_scheduler',
+        'action_id' => 47,
+    ]);
+    assert_same(
+        'https://translate.example.test/translations/',
+        $mapped_payload->site_url,
+        'Payload URL must prefer a uniquely owned active domain mapping'
+    );
+
+    $GLOBALS['test_mapping_row'] = null;
+    $GLOBALS['test_canonical_mapping_conflicts'] = 1;
+    $unroutable_payload = new Job_Payload([
+        'hook' => 'unroutable_site_hook',
+        'timestamp' => 1710000000,
+        'source' => 'action_scheduler',
+        'action_id' => 48,
+    ]);
+    assert_same('', $unroutable_payload->site_url, 'A canonical domain mapped to another blog must fail closed');
+    \Workerman\Worker::$logs = [];
+    invoke_private($worker, 'schedule_timer', [$unroutable_payload]);
+    invoke_private($worker, 'schedule_timer', [$unroutable_payload]);
+    assert_same(1, count(\Workerman\Worker::$logs), 'An unroutable site must be skipped with one bounded diagnostic');
+
+    $GLOBALS['test_mapping_table_exists'] = false;
+    $GLOBALS['test_canonical_mapping_conflicts'] = 0;
     restore_current_blog();
     $GLOBALS['test_site_url'] = 'https://example.test';
     $GLOBALS['test_site_domain'] = 'example.test';