diff --git a/backend/crates/providers/openai/src/credential/selector.rs b/backend/crates/providers/openai/src/credential/selector.rs
index 14066f10b..1bad92ccb 100644
--- a/backend/crates/providers/openai/src/credential/selector.rs
+++ b/backend/crates/providers/openai/src/credential/selector.rs
@@ -480,17 +480,18 @@ impl CodexCredentialSelector {
             && request
                 .session_affinity_observation
                 .is_some_and(CodexSessionAffinity::follow_only);
-        let select = |queue_policy| {
+        let select = |queue_policy, queue_rejection| {
             self.select_inner_loop(
                 request,
                 cyber_policy_session_key,
                 model,
                 follow_only,
                 queue_policy,
+                queue_rejection,
             )
         };
         let selection = async {
-            let rejection = match select(policy.queue_policy()).await {
+            let rejection = match select(policy.queue_policy(), None).await {
                 Err(CredentialSelectionError::QueueRejected(reason))
                     if !follow_only
                         && request.attempt.required_account().is_none()
@@ -512,7 +513,7 @@ impl CodexCredentialSelector {
                             "account.queue.reselect",
                             serde_json::json!({"reason": rejection.to_string()}),
                         );
-                        select(queue)
+                        select(queue, Some(rejection))
                     },
                     |err| {
                         matches!(
@@ -555,6 +556,7 @@ impl CodexCredentialSelector {
         model: CodexSelectionModel<'_>,
         follow_only: bool,
         mut queue_policy: ConcurrencyQueuePolicy,
+        queue_rejection: Option<QueueRejection>,
     ) -> Result<CodexCredentialLease, CredentialSelectionError> {
         let adapter_model = match model {
             CodexSelectionModel::Requested(model) if request.managed_upstream => Some(
@@ -1351,7 +1353,30 @@ impl CodexCredentialSelector {
                                     tracing::warn!(%error, "OpenAI cache preference update unavailable");
                                 }
                                 Err(error) => return Err(error),
-                                Ok(true) => {}
+                                Ok(true) => {
+                                    if let Some(reason) = queue_rejection
+                                        && let Some(previous) = binding.as_ref().filter(|binding| {
+                                            binding.account_id() != binding_account
+                                        })
+                                    {
+                                        tracing::info!(
+                                            request_id = %request.attempt.request_id(),
+                                            attempt_index = request.attempt.attempt_index().get(),
+                                            reason = %reason,
+                                            from_account_id = %previous.account_id(),
+                                            to_account_id = %binding_account,
+                                            "OpenAI 账号排队失败后已迁移绑定"
+                                        );
+                                        request.attempt.trace().record_evidence(
+                                            "account.binding.migrated",
+                                            serde_json::json!({
+                                                "reason": reason.to_string(),
+                                                "fromAccountId": previous.account_id().as_str(),
+                                                "toAccountId": binding_account.as_str(),
+                                            }),
+                                        );
+                                    }
+                                }
                             }
                         }
                         let affinity_telemetry = affinity.telemetry(account.id(), cache_preference);
diff --git a/backend/crates/providers/openai/tests/credential/contract/scheduling_projection.rs b/backend/crates/providers/openai/tests/credential/contract/scheduling_projection.rs
index a00a146d1..8d75ba411 100644
--- a/backend/crates/providers/openai/tests/credential/contract/scheduling_projection.rs
+++ b/backend/crates/providers/openai/tests/credential/contract/scheduling_projection.rs
@@ -18,7 +18,10 @@ fn projection_attempt(
         RequestAttemptContext::new(
             ModelRequestId::new("req_projection").unwrap(),
             ClientApiKeyId::new(client_key).unwrap(),
-        ),
+        )
+        .with_trace(gateway_core::diagnostics::TraceContext::new(
+            "req_projection",
+        )),
         NonZeroU32::new(1).unwrap(),
         SystemTime::now() + Duration::from_secs(30),
         policy,
@@ -420,15 +423,35 @@ async fn strict_queue_failure_reselects_once_and_only_rebinds_after_admission()
             assert!(pending.as_mut().now_or_never().is_none());
         }
         let result = pending.await;
+        let reason = if full {
+            QueueRejection::Full
+        } else {
+            QueueRejection::Timeout
+        };
+        let snapshot = ctx.trace().snapshot().unwrap();
+        let migrations = snapshot["events"]
+            .as_array()
+            .unwrap()
+            .iter()
+            .filter(|event| event["stage"] == "account.binding.migrated")
+            .map(|event| &event["data"])
+            .collect::<Vec<_>>();
+        if spare && enabled {
+            assert_eq!(
+                migrations,
+                vec![&json!({
+                    "reason": reason.to_string(),
+                    "fromAccountId": first.as_str(),
+                    "toAccountId": second.as_str(),
+                })]
+            );
+        } else {
+            assert!(migrations.is_empty());
+        }
         let expected = if spare && enabled {
             assert_eq!(result.unwrap().account_id(), &second);
             &second
         } else {
-            let reason = if full {
-                QueueRejection::Full
-            } else {
-                QueueRejection::Timeout
-            };
             assert!(
                 matches!(result, Err(CredentialSelectionError::QueueRejected(actual)) if actual == reason)
             );
diff --git a/docs/api.md b/docs/api.md
index 7feb2525d..07e0014cb 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -2762,6 +2762,10 @@ WebSocket 握手不主动添加专项计时请求头，客户端显式提供的
 `environment.scope = export_time` 明确版本、构建与部署信息是导出时状态，不能代替事发环境
 
 `request.routed.data.accountPolicy` 保存执行时冻结的账号策略与预算。
+OpenAI 账号队满或超时后的重选记录为 `account.queue.reselect`；绑定迁移成功后，
+`account.binding.migrated` 保存拒绝原因 `reason`、原账号 `fromAccountId` 和新账号 `toAccountId`。
+首次认领、临时分流和失败重选不记录为绑定迁移
+
 `attempt.failed.data.recovery` 保存 Provider 的重放安全性和恢复意图；`retry.decided` 保存当时
 实际参与决策的门槛、剩余预算和发送状态，`retry.policy` 保存宿主及插件策略的停止事实。
 已有的 `provider.precommit.released` 数据保留释放原因、预取字节数与等待时间，不等同于下游已提交