diff --git a/sanguo_factor/data_gap_check.py b/sanguo_factor/data_gap_check.py
index 1d69e029..d4115087 100644
--- a/sanguo_factor/data_gap_check.py
+++ b/sanguo_factor/data_gap_check.py
@@ -16,12 +16,15 @@ import argparse
 import hashlib
 import json
 import os
+import re
 import sys
+from datetime import date
 from typing import Any
 
 import yaml
 
-from sanguo_factor.version_registry import load_registry, open_gitea_issue
+from sanguo_factor.version_registry import GITEA_BASE_URL, load_registry, \
+    open_gitea_issue
 
 
 def load_manifest(path: str) -> dict[str, Any]:
@@ -67,35 +70,120 @@ def render_gap_issue(gaps: dict[str, list[str]], manifest_path: str) -> tuple[st
     return title, "\n".join(body)
 
 
+class GiteaLookupError(RuntimeError):
+    """open issue 查询网络异常(≠「确认不存在」)——调用方须跳过开单本月."""
+
+
+# 指纹本地台账(append-only,每行一 JSON):第二道去重,网络盲区/失明时兜底.
+GAP_ISSUE_LEDGER = "data/gap_issue_ledger.jsonl"
+
+
 def find_open_issue(title: str, token: str, base_url: str | None = None,
                     repo: str = "sanguo/sanguo_vnpy_v2") -> int | None:
-    """精确标题匹配 open issue(仓库 issue 量小,首页 50 足够;失败返 None)."""
+    """精确标题匹配 open issue,双层查询(P2-13①).
+
+    首页 LIST 50 条精确匹配→未中再 search API 兜底(按标题指纹 sha1 前 8 位
+    搜,破「目标单跌出首页→静默失明→同指纹月月重复开单」)。
+    返回 None=双层皆空=确认不存在;LIST/search 任一网络异常抛
+    GiteaLookupError(≠不存在,调用方异常时跳过开单本月,下月再试)。
+    """
+    import urllib.parse
     import urllib.request
     if base_url is None:
-        base_url = os.environ.get("SANGUO_GITEA_BASE_URL",
-                                  "http://192.168.2.154:3000")
-    url = f"{base_url}/api/v1/repos/{repo}/issues?state=open&type=issues&limit=50"
-    req = urllib.request.Request(url, headers={"Authorization": f"token {token}"})
-    try:
+        base_url = os.environ.get("SANGUO_GITEA_BASE_URL", GITEA_BASE_URL)
+
+    def _get(url: str) -> list:
+        req = urllib.request.Request(
+            url, headers={"Authorization": f"token {token}"})
         with urllib.request.urlopen(req, timeout=15) as resp:
-            for it in json.loads(resp.read().decode("utf-8")):
-                if it.get("title") == title:
-                    return it["number"]
-    except Exception:
-        return None
+            return json.loads(resp.read().decode("utf-8"))
+
+    try:
+        list_url = (f"{base_url}/api/v1/repos/{repo}/issues"
+                    "?state=open&type=issues&limit=50")
+        for it in _get(list_url):
+            if it.get("title") == title:
+                return it["number"]
+        m = re.search(r"\[([0-9a-f]{8})\]", title)
+        q = m.group(1) if m else title
+        search_url = (f"{base_url}/api/v1/repos/{repo}/issues"
+                      f"?state=open&type=issues&q={urllib.parse.quote(q)}")
+        for it in _get(search_url):
+            if it.get("title") == title:
+                return it["number"]
+    except GiteaLookupError:
+        raise
+    except Exception as e:
+        raise GiteaLookupError(str(e)) from e
     return None
 
 
+def load_ledger_fps(path: str) -> set[str]:
+    """台账已开指纹集合(坏行/空行跳过;文件缺=空集;读失败降级空集+stderr)."""
+    if not os.path.exists(path):
+        return set()
+    fps: set[str] = set()
+    try:
+        with open(path, encoding="utf-8") as f:
+            for line in f:
+                line = line.strip()
+                if not line:
+                    continue
+                try:
+                    fp = json.loads(line).get("fingerprint")
+                except json.JSONDecodeError:
+                    continue
+                if fp:
+                    fps.add(fp)
+    except OSError as e:
+        print(f"[data_gap_check] 台账读取失败(降级视为空集): {e}", file=sys.stderr)
+    return fps
+
+
+def append_ledger(path: str, fingerprint: str, issue_number: int,
+                  opened_at: str) -> None:
+    """台账 append 一行(指纹/issue号/日期);写失败 stderr 降级不阻断开单."""
+    try:
+        os.makedirs(os.path.dirname(path) or ".", exist_ok=True)
+        with open(path, "a", encoding="utf-8") as f:
+            f.write(json.dumps({"fingerprint": fingerprint,
+                                "issue": issue_number,
+                                "opened_at": opened_at},
+                               ensure_ascii=False) + "\n")
+    except OSError as e:
+        print(f"[data_gap_check] 台账写入失败(降级不阻断): {e}", file=sys.stderr)
+
+
 def maybe_open_gap_issue(gaps: dict[str, list[str]],
-                         manifest_path: str) -> int | None:
-    """有 token 且同指纹无 open 单才开;一切失败静默降级返 None(告警不依赖网络)."""
+                         manifest_path: str,
+                         ledger_path: str = GAP_ISSUE_LEDGER) -> int | None:
+    """有 token 且同指纹无 open 单(台账+网络双层去重)才开;失败降级返 None.
+
+    去重三重(P2-13): ①本地台账命中→跳过不打网络;②open issue 双层查询
+    (首页 LIST+search 兜底)命中→跳过;③查询网络异常→跳过开单本月
+    (stderr 留痕,下月再试)——只有「确认不存在」才真正开单,
+    开单成功后回写台账。
+    """
     token = os.environ.get("SANGUO_GITEA_TOKEN")
     if not token:
         return None
-    title, body = render_gap_issue(gaps, manifest_path)
-    if find_open_issue(title, token) is not None:
+    fp = gap_fingerprint(gaps)
+    if fp in load_ledger_fps(ledger_path):
+        print(f"[data_gap_check] 台账命中指纹 {fp}(issue 已开过),跳过开单",
+              file=sys.stderr)
         return None
-    return open_gitea_issue(title, body, token)
+    title, body = render_gap_issue(gaps, manifest_path)
+    try:
+        if find_open_issue(title, token) is not None:
+            return None
+    except GiteaLookupError as e:
+        print(f"[data_gap_check] Gitea 查询异常,本月跳过开单(下月再试): {e}",
+              file=sys.stderr)
+        return None
+    num = open_gitea_issue(title, body, token)
+    if num:
+        append_ledger(ledger_path, fp, num, date.today().isoformat())
+    return num
 
 
 def main(argv: list[str] | None = None) -> int:
diff --git a/sanguo_factor/version_registry.py b/sanguo_factor/version_registry.py
index 4664da14..eec46095 100644
--- a/sanguo_factor/version_registry.py
+++ b/sanguo_factor/version_registry.py
@@ -21,6 +21,10 @@ import yaml
 VALID_STATUSES = frozenset(
     {"incubating", "assessable", "promoted", "decaying", "retired", "graveyard"})
 
+# 内网 Gitea 缺省地址(B' 双机: NAS=内网 IP, VPS=FRP 127.0.0.1:13000)——
+# 单源常量,data_gap_check 等同仓消费方 import 此处,禁再抄字面量(P3-20).
+GITEA_BASE_URL = "http://192.168.2.154:3000"
+
 # 合法迁移:普通链路逐级+跳过 assessable 的快车道不存在;graveyard 终态不可复活.
 _VALID_TRANSITIONS: dict[str, frozenset[str]] = {
     "incubating": frozenset({"assessable", "graveyard"}),
@@ -216,8 +220,7 @@ def open_gitea_issue(title: str, body: str, token: str,
     """
     import urllib.request
     if base_url is None:
-        base_url = os.environ.get("SANGUO_GITEA_BASE_URL",
-                                  "http://192.168.2.154:3000")
+        base_url = os.environ.get("SANGUO_GITEA_BASE_URL", GITEA_BASE_URL)
     url = f"{base_url}/api/v1/repos/{repo}/issues"
     payload = json.dumps({"title": title, "body": body}).encode("utf-8")
     req = urllib.request.Request(
diff --git a/tests/factor/test_data_gap_check.py b/tests/factor/test_data_gap_check.py
index ae5a6c72..52708ad5 100644
--- a/tests/factor/test_data_gap_check.py
+++ b/tests/factor/test_data_gap_check.py
@@ -69,25 +69,29 @@ def test_render_gap_issue_shape():
     assert "data session" in body
 
 
-def test_maybe_open_dedup_skips_existing(monkeypatch):
+def test_maybe_open_dedup_skips_existing(monkeypatch, tmp_path):
     import sanguo_factor.data_gap_check as dgc
     monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
     monkeypatch.setattr(dgc, "find_open_issue", lambda *a, **k: 42)
     opened = []
     monkeypatch.setattr(dgc, "open_gitea_issue",
                         lambda *a, **k: opened.append(a) or 99)
-    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml") is None
+    assert dgc.maybe_open_gap_issue(
+        {"fa_x": ["s_new"]}, "m.yaml",
+        ledger_path=str(tmp_path / "ledger.jsonl")) is None
     assert opened == []                                  # 同指纹在册→跳过
 
 
-def test_maybe_open_creates_when_absent(monkeypatch):
+def test_maybe_open_creates_when_absent(monkeypatch, tmp_path):
     import sanguo_factor.data_gap_check as dgc
     monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
     monkeypatch.setattr(dgc, "find_open_issue", lambda *a, **k: None)
     opened = []
     monkeypatch.setattr(dgc, "open_gitea_issue",
                         lambda title, body, token, **k: opened.append(title) or 7)
-    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml") == 7
+    assert dgc.maybe_open_gap_issue(
+        {"fa_x": ["s_new"]}, "m.yaml",
+        ledger_path=str(tmp_path / "ledger.jsonl")) == 7
     assert opened and opened[0].startswith("[数据缺口]")
 
 
@@ -116,3 +120,173 @@ def test_find_open_issue_matches_exact_title(monkeypatch):
     monkeypatch.setattr(urllib.request, "urlopen", lambda req, timeout=None: FakeResp())
     assert dgc.find_open_issue("[数据缺口] 1 因子待接源 [abcd1234]", "tok") == 11
     assert dgc.find_open_issue("不在册标题", "tok") is None
+
+
+# —— P2-13 三重加固: search 兜底/异常≠不存在/本地台账 + P3-20 地址单源 ——
+import json as _json
+
+
+class _JsonResp:
+    """按给定 items 回 JSON 的 urlopen 假响应."""
+
+    def __init__(self, items):
+        self._items = items
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *a):
+        return False
+
+    def read(self):
+        return _json.dumps(self._items).encode()
+
+
+def test_gitea_base_url_single_source():
+    """P3-20: data_gap_check 的内网地址必须 import 自 version_registry(同一对象)."""
+    import sanguo_factor.data_gap_check as dgc
+    import sanguo_factor.version_registry as vr
+    assert dgc.GITEA_BASE_URL is vr.GITEA_BASE_URL
+    assert vr.GITEA_BASE_URL == "http://192.168.2.154:3000"
+
+
+def test_find_open_issue_list_hit_no_search(monkeypatch):
+    import sanguo_factor.data_gap_check as dgc
+    urls = []
+
+    def fake(req, timeout=None):
+        urls.append(req.full_url)
+        return _JsonResp([{"number": 3,
+                           "title": "[数据缺口] 1 因子待接源 [abcd1234]"}])
+
+    monkeypatch.setattr("urllib.request.urlopen", fake)
+    assert dgc.find_open_issue(
+        "[数据缺口] 1 因子待接源 [abcd1234]", "tok") == 3
+    assert len(urls) == 1 and "limit=50" in urls[0]      # 首页命中不触发 search
+
+
+def test_find_open_issue_search_fallback_beyond_first_page(monkeypatch):
+    """首页 50 条塞满他人单,目标单在首页外——search API 按指纹兜底命中."""
+    import sanguo_factor.data_gap_check as dgc
+    title = "[数据缺口] 1 因子待接源 [abcd1234]"
+    urls = []
+
+    def fake(req, timeout=None):
+        urls.append(req.full_url)
+        if "limit=50" in req.full_url:
+            return _JsonResp([{"number": i, "title": f"占位单{i}"}
+                              for i in range(50)])
+        return _JsonResp([{"number": 88, "title": title}])
+
+    monkeypatch.setattr("urllib.request.urlopen", fake)
+    assert dgc.find_open_issue(title, "tok") == 88
+    assert len(urls) == 2
+    assert "q=abcd1234" in urls[1]                       # search 按指纹兜底
+
+
+def test_find_open_issue_both_miss_confirmed_absent(monkeypatch):
+    import sanguo_factor.data_gap_check as dgc
+
+    def fake(req, timeout=None):
+        return _JsonResp([])
+
+    monkeypatch.setattr("urllib.request.urlopen", fake)
+    assert dgc.find_open_issue("不在册标题", "tok") is None  # 双 miss=确认不存在
+
+
+def test_find_open_issue_list_error_raises_not_none(monkeypatch):
+    """LIST 网络异常≠不存在——抛 GiteaLookupError 供调用方跳过开单."""
+    import pytest
+
+    import sanguo_factor.data_gap_check as dgc
+
+    def boom(req, timeout=None):
+        raise OSError("connection refused")
+
+    monkeypatch.setattr("urllib.request.urlopen", boom)
+    with pytest.raises(dgc.GiteaLookupError):
+        dgc.find_open_issue("[数据缺口] 1 因子待接源 [abcd1234]", "tok")
+
+
+def test_find_open_issue_search_error_raises(monkeypatch):
+    """search 异常同义:异常≠空,归 GiteaLookupError(调用方跳过开单本月)."""
+    import pytest
+
+    import sanguo_factor.data_gap_check as dgc
+
+    def fake(req, timeout=None):
+        if "limit=50" in req.full_url:
+            return _JsonResp([])
+        raise OSError("search timeout")
+
+    monkeypatch.setattr("urllib.request.urlopen", fake)
+    with pytest.raises(dgc.GiteaLookupError):
+        dgc.find_open_issue("[数据缺口] 1 因子待接源 [abcd1234]", "tok")
+
+
+def test_maybe_open_skips_on_lookup_error(monkeypatch, tmp_path, capsys):
+    """LIST 异常时跳过开单本月(stderr 留痕,下月再试),不再 fail-open."""
+    import sanguo_factor.data_gap_check as dgc
+
+    def boom(*a, **k):
+        raise dgc.GiteaLookupError("conn refused")
+
+    monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
+    monkeypatch.setattr(dgc, "find_open_issue", boom)
+    opened = []
+    monkeypatch.setattr(dgc, "open_gitea_issue",
+                        lambda *a, **k: opened.append(a) or 99)
+    ledger = str(tmp_path / "ledger.jsonl")
+    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml",
+                                    ledger_path=ledger) is None
+    assert opened == []                                  # 异常不开单
+    assert "跳过开单" in capsys.readouterr().err          # stderr 留痕
+
+
+def test_maybe_open_ledger_hit_skips_before_network(monkeypatch, tmp_path,
+                                                    capsys):
+    """台账第二道去重:指纹命中即跳过,不再打网络."""
+    import sanguo_factor.data_gap_check as dgc
+    fp = dgc.gap_fingerprint({"fa_x": ["s_new"]})
+    ledger = tmp_path / "ledger.jsonl"
+    ledger.write_text(_json.dumps(
+        {"fingerprint": fp, "issue": 42, "opened_at": "2026-10-01"}) + "\n",
+        encoding="utf-8")
+
+    def no_network(*a, **k):
+        raise AssertionError("台账命中后不应再触网")
+
+    monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
+    monkeypatch.setattr(dgc, "find_open_issue", no_network)
+    monkeypatch.setattr(dgc, "open_gitea_issue", no_network)
+    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml",
+                                    ledger_path=str(ledger)) is None
+    assert "台账命中" in capsys.readouterr().err
+
+
+def test_maybe_open_appends_ledger_after_opening(monkeypatch, tmp_path):
+    """开单成功→台账 append 一行(指纹/issue号/日期三键)."""
+    import sanguo_factor.data_gap_check as dgc
+    monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
+    monkeypatch.setattr(dgc, "find_open_issue", lambda *a, **k: None)
+    monkeypatch.setattr(dgc, "open_gitea_issue", lambda *a, **k: 77)
+    ledger = tmp_path / "sub" / "ledger.jsonl"           # 父目录不存在也建
+    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml",
+                                    ledger_path=str(ledger)) == 77
+    rec = _json.loads(ledger.read_text(encoding="utf-8").strip())
+    assert rec["fingerprint"] == dgc.gap_fingerprint({"fa_x": ["s_new"]})
+    assert rec["issue"] == 77 and rec["opened_at"]
+
+
+def test_append_ledger_failure_degrades_not_blocks(monkeypatch, tmp_path,
+                                                   capsys):
+    """台账写失败(此处:路径是目录)不阻断开单主流程,stderr 降级留痕."""
+    import sanguo_factor.data_gap_check as dgc
+    monkeypatch.setenv("SANGUO_GITEA_TOKEN", "tok")
+    monkeypatch.setattr(dgc, "find_open_issue", lambda *a, **k: None)
+    monkeypatch.setattr(dgc, "open_gitea_issue", lambda *a, **k: 77)
+    bad_ledger = tmp_path / "its_a_dir"                  # makedirs 会成功,open 会失败
+    bad_ledger.mkdir()
+    assert dgc.maybe_open_gap_issue({"fa_x": ["s_new"]}, "m.yaml",
+                                    ledger_path=str(bad_ledger)) == 77
+    assert "台账写入失败" in capsys.readouterr().err