diff --git a/engine.go b/engine.go
index 9abbf93..9f12aad 100644
--- a/engine.go
+++ b/engine.go
@@ -531,6 +531,7 @@ func (e *Engine) syncOnce(s *repoState, trigger string) {
 	// 分支对齐：本地当前分支与配置不一致时，自动切换/创建（对齐原 bash 脚本行为）
 	// 否则 push 会因 src refspec 不存在而失败
 	if cur, cerr := currentBranch(cfg.RepoPath); cerr == nil && cur != cfg.Branch {
+		tip, remoteHasBranch := remoteTip(cfg.RepoPath, remote, cfg.Branch)
 		switch {
 		case branchExists(cfg.RepoPath, cfg.Branch):
 			if _, err := gitRun(cfg.RepoPath, 30*time.Second, "checkout", cfg.Branch); err != nil {
@@ -538,12 +539,12 @@ func (e *Engine) syncOnce(s *repoState, trigger string) {
 			} else {
 				e.logf(s, "info", "本地分支与配置不一致（%s → %s），已自动切换", cur, cfg.Branch)
 			}
-		case remoteRefExists(cfg.RepoPath, remote, cfg.Branch):
-			if _, err := gitRun(cfg.RepoPath, 30*time.Second, "checkout", "-B", cfg.Branch, remote+"/"+cfg.Branch); err != nil {
-				e.logf(s, "warn", "基于 %s/%s 创建分支失败: %v（继续在 %s 上同步）", remote, cfg.Branch, err, cur)
+		case remoteHasBranch:
+			if _, err := gitRun(cfg.RepoPath, 30*time.Second, "checkout", "-B", cfg.Branch, tip); err != nil {
+				e.logf(s, "warn", "基于远程 %s 创建分支失败: %v（继续在 %s 上同步）", cfg.Branch, err, cur)
 			} else {
 				_, _ = gitRun(cfg.RepoPath, 15*time.Second, "branch", "--set-upstream-to", remote+"/"+cfg.Branch, cfg.Branch)
-				e.logf(s, "info", "本地无分支 %s，已基于 %s/%s 创建并跟踪", cfg.Branch, remote, cfg.Branch)
+				e.logf(s, "info", "本地无分支 %s，已基于远程 %s（%s）创建并跟踪", cfg.Branch, cfg.Branch, tip[:8])
 			}
 		default:
 			if _, err := gitRun(cfg.RepoPath, 30*time.Second, "checkout", "-B", cfg.Branch); err != nil {
@@ -576,8 +577,9 @@ func (e *Engine) syncOnce(s *repoState, trigger string) {
 
 	var ahead, behind int
 	var err error
-	if remoteRefExists(cfg.RepoPath, remote, cfg.Branch) {
-		ahead, behind, err = aheadBehind(cfg.RepoPath, remote, cfg.Branch)
+	tip, remoteHasBranch := remoteTip(cfg.RepoPath, remote, cfg.Branch)
+	if remoteHasBranch {
+		ahead, behind, err = aheadBehindSha(cfg.RepoPath, tip)
 		if err != nil {
 			e.setFail(s, "获取领先/落后信息失败: "+err.Error())
 			return
diff --git a/git.go b/git.go
index c1dd787..91ab1d3 100644
--- a/git.go
+++ b/git.go
@@ -87,6 +87,42 @@ func branchExists(path, branch string) bool {
 	return err == nil
 }
 
+// remoteTip 返回远程分支当前指向的 SHA。
+// 优先读本地远程跟踪引用（refs/remotes/<remote>/<branch>，快）；
+// 若本地跟踪引用不可用（个别环境下 ref 存储读写异常），回退用 ls-remote 直查远程。
+func remoteTip(path, remote, branch string) (sha string, exists bool) {
+	if remoteRefExists(path, remote, branch) {
+		out, err := gitRun(path, 15*time.Second, "rev-parse", remote+"/"+branch)
+		if err == nil {
+			return strings.TrimSpace(out), true
+		}
+	}
+	out, err := gitRun(path, 30*time.Second, "ls-remote", remote, "refs/heads/"+branch)
+	if err != nil {
+		return "", false
+	}
+	fields := strings.Fields(strings.TrimSpace(out))
+	if len(fields) < 2 {
+		return "", false
+	}
+	return fields[0], true
+}
+
+// aheadBehindSha 基于远程分支的具体 SHA 计算 (领先, 落后)，不依赖本地跟踪引用
+func aheadBehindSha(path, tip string) (int, int, error) {
+	out, err := gitRun(path, 30*time.Second, "rev-list", "--left-right", "--count", "HEAD..."+tip)
+	if err != nil {
+		return 0, 0, err
+	}
+	parts := strings.Fields(out)
+	if len(parts) != 2 {
+		return 0, 0, fmt.Errorf("无法解析 rev-list 输出: %q", out)
+	}
+	a, _ := strconv.Atoi(parts[0])
+	b, _ := strconv.Atoi(parts[1])
+	return a, b, nil
+}
+
 func dirtyCount(path string) int {
 	out, err := gitRun(path, 30*time.Second, "status", "--porcelain")
 	if err != nil {
diff --git a/logs/git-auto-sync.log b/logs/git-auto-sync.log
index e341236..477b6b1 100644
--- a/logs/git-auto-sync.log
+++ b/logs/git-auto-sync.log
@@ -175,3 +175,10 @@ hint: See the 'Note about fast-forwards' in 'git push --help' for details.
 [2026-09-08 18:13:59] 推送失败，本轮同步已终止（跳过拉取以避免分叉加剧）
 [2026-09-08 18:14:59] === 开始同步（定时检查，模式 push）===
 [2026-09-08 18:15:09] 检测到 2 个未提交改动，执行自动提交
+[2026-09-08 18:15:13] 自动提交完成，将随本轮同步推送
+[2026-09-08 18:15:15] 远程分支 origin/main 不存在（远程仓库可能为空或分支名不一致），将推送本地 23 个提交以建立远程分支
+[2026-09-08 18:20:25] 推送至 origin 失败: 命令超时: git push origin main
+[2026-09-08 18:20:25] 推送失败，本轮同步已终止（跳过拉取以避免分叉加剧）
+[2026-09-08 18:21:31] 监控已启动
+[2026-09-08 18:21:31] === 开始同步（启动检查，模式 push）===
+[2026-09-08 18:21:40] 检测到 4 个未提交改动，执行自动提交
diff --git a/stats/git-auto-sync.csv b/stats/git-auto-sync.csv
index 33b0eec..6371d75 100644
--- a/stats/git-auto-sync.csv
+++ b/stats/git-auto-sync.csv
@@ -20,3 +20,4 @@ timestamp,action,result,commits
 2026-09-08 18:01:06,push,failed,20
 2026-09-08 18:07:32,push,failed,21
 2026-09-08 18:13:59,push,failed,22
+2026-09-08 18:20:25,push,failed,23