diff --git a/inbound_verify/cli/server.py b/inbound_verify/cli/server.py
index 1ae282d..0169d85 100644
--- a/inbound_verify/cli/server.py
+++ b/inbound_verify/cli/server.py
@@ -17,7 +17,7 @@ import queue
 import threading
 import time
 from contextlib import asynccontextmanager
-from datetime import datetime
+from datetime import datetime, timedelta
 from typing import Dict, Optional
 
 import uvicorn
@@ -190,11 +190,12 @@ class TaskRequest(BaseModel):
     force: bool = (
         False  # 强制重下：忽略已落库去重，重新提交所有班次/交接单的导出任务（默认关）
     )
+    date: Optional[str] = None  # YYYY-MM-DD；指定则下载该日数据，否则走站点 offset
 
 
 @app.post("/tasks")
 def create_task(req: TaskRequest):
-    """提交任务 {site, kind} → 入队，返回 task_id。"""
+    """提交任务 {site, kind, force, date?} → 入队，返回 task_id。"""
     # 【P0】后端未就绪时直接拒绝，避免任务在 worker 启动前入队卡死
     if not worker_state["ready"]:
         raise HTTPException(
@@ -202,8 +203,32 @@ def create_task(req: TaskRequest):
         )
     if (req.site, req.kind) not in TASK_HANDLERS:
         raise HTTPException(status_code=400, detail=f"无效任务: {req.site}/{req.kind}")
+    # 指定日期合法性校验（仅在传了 date 时）
+    if req.date:
+        try:
+            target_date = datetime.strptime(req.date, "%Y-%m-%d").date()
+        except ValueError:
+            raise HTTPException(
+                status_code=400, detail=f"date 格式非法，需 YYYY-MM-DD: {req.date}"
+            )
+        today = datetime.now().date()
+        if target_date > today:
+            raise HTTPException(
+                status_code=400, detail=f"date 不可为未来日期: {req.date}"
+            )
+        if target_date < today - timedelta(days=90):
+            raise HTTPException(
+                status_code=400, detail=f"date 超出 90 天回溯上限: {req.date}"
+            )
+        if req.site == "百世":
+            raise HTTPException(
+                status_code=400, detail="百世固定下载当天，不支持指定日期"
+            )
     task_id = state_store.create_task(req.site, req.kind)
-    task_queue.put((task_id, {"site": req.site, "kind": req.kind, "force": req.force}))
+    spec = {"site": req.site, "kind": req.kind, "force": req.force}
+    if req.date:
+        spec["date"] = req.date
+    task_queue.put((task_id, spec))
     return {"task_id": task_id}