diff --git a/docs/data-model.md b/docs/data-model.md
index 3819559..681c09e 100644
--- a/docs/data-model.md
+++ b/docs/data-model.md
@@ -49,7 +49,7 @@
 - limit_price :: numeric? :: 현재 pending 주문 지정가(side 무관, dcy-012/REQ-002 — 과거 `entry_price`에서 rename). pending 진입(매수/매도 지정가) 시 set, pending 이탈(→holding/→closed) 시 None 으로 clear → 매수 지정가가 매도로 누수되지 않음(issue #10). None 이면 dispatch 시 시장가.
 - allocated_capital :: numeric? :: 배정 자본
 - order_id / broker_order_id :: str? :: 주문 식별자(자유 주석 / 브로커 핸들)
-- venue :: TEXT NOT NULL DEFAULT 'KRX' :: 현재 주문 거래소 구분(AUTO/KRX/NXT/SOR). intent 단계의 AUTO는 KIS 제출 시 실제 KRX/NXT로 교체되며 주문번호와 원자 저장한다. pending 주문·취소까지 보존하고 HOLDING 진입 시 다음 자율주문의 AUTO, INACTIVE 진입 시 KRX로 초기화한다.
+- venue :: TEXT NOT NULL DEFAULT 'KRX' :: 현재 주문 거래소 구분(KRX/NXT/SOR). venue 누락 intent는 SOR로 저장하고, 명시 venue는 보존한다. pending 주문·취소까지 보존하며 HOLDING 진입 시 다음 주문의 SOR, INACTIVE 진입 시 KRX로 초기화한다.
 - cancel_state :: TEXT? :: 취소 요청의 즉시 결과(requested/rejected/unknown). 최종 취소 상태가 아니다. requested는 재시도하지 않고, rejected/unknown만 authoritative open-row 확인과 bounded backoff 뒤 재시도할 수 있다.
 - cancel_requested_at :: TIMESTAMPTZ? :: 마지막 취소 시도 예약 시각. 주문 종료·dispatch clear 때 함께 제거한다.
 - order_submitted_at :: TIMESTAMPTZ? :: timeout deadline의 immutable 주문 제출 기준점. poll/cancel bookkeeping 및 daemon 재시작에서 보존하고 terminal dispatch clear 때 제거한다.
diff --git a/docs/interface-contract.md b/docs/interface-contract.md
index 1df6911..10b813d 100644
--- a/docs/interface-contract.md
+++ b/docs/interface-contract.md
@@ -64,7 +64,7 @@
 | 패턴 | 표면 | 요청 속성 | 응답 |
 |---|---|---|---|
 | 슬롯 RPC | `trex.slots.req` | `correlation_id`, `reply_to=amq.rabbitmq.reply-to` | reply-to 큐로 `{slots[], degraded, reason, message}` (REQ-073/074, BAT-035) |
-| intent RPC | `trex.intent.req` | `correlation_id` = intent 멱등키, `reply_to=amq.rabbitmq.reply-to`, `delivery_mode=2` | reply-to 큐로 `{intent_id, status:admitted|rejected, slot_id?, reason?}`. **rejected sell** 응답은 additive `retryable: bool` 포함(REQ-007 AC-7/issue #27 — core 소유 reason→retryable, 미인식 기본 true, `bad_request:*` false; admitted/processing/buy 는 미포함). 체결/종료는 응답 아닌 이벤트로 |
+| intent RPC | `trex.intent.req` | `correlation_id` = intent 멱등키, `reply_to=amq.rabbitmq.reply-to`, `delivery_mode=2` | reply-to 큐로 `{intent_id, status:admitted|rejected, slot_id?, reason?}`. retryability·broker attempt·KIS failure 정보는 strategy 응답에 포함하지 않는다. 체결/종료는 응답 아닌 이벤트로 |
 | update_thresholds | `trex.intent.req` | `action="update_thresholds"`, `reply_to` | reply-to 큐로 `{status:updated|ignored, slot_id, reason?}` (REQ-040) |
 | 이벤트 pub/sub | `trex.events` (topic) | routing key `{event_type}.{strategy_id}.{symbol}` | 전략 큐가 자기 `strategy_id` 패턴으로 바인딩 |
 
@@ -415,8 +415,8 @@ resume_kill_switch 요청·응답 (REQ-046):
 ### Additive Notes (REQ-117)
 
 - `venue` 필드는 BAT-056에서 additive 추가. 기존 orb/tsl 미지정 호출 → 기본값 `"KRX"` 자동 적용 → 하위 호환.
-- `OrderRequest`는 AMQP wire 위를 직접 흐르지 않는다. buy/sell intent의 선택적 `venue` 기본은 `AUTO`이고, 명시한 KRX/NXT/SOR는 그대로 슬롯에 보존한다. 허용값 외에는 `invalid_venue`로 admission 전 거부한다.
-- KIS 어댑터는 `AUTO`를 KST 세션 기준 실제 KRX/NXT로 확정한 뒤 `EXCG_ID_DVSN_CD`로 전송한다. 결정 불가능 구간은 KRX로 대체하지 않고 주문을 거부한다.
+- `OrderRequest`는 AMQP wire 위를 직접 흐르지 않는다. buy/sell intent의 선택적 `venue` 누락은 `SOR`이고, 명시한 KRX/NXT/SOR는 그대로 슬롯에 보존한다. `AUTO`와 그 밖의 값은 `invalid_venue`로 admission 전 거부한다.
+- KIS 어댑터는 KRX/NXT/SOR를 시간과 무관하게 보존해 `EXCG_ID_DVSN_CD`로 전송한다.
 - `OrderAck.venue`의 실제 제출 거래소는 `broker_order_id`와 함께 슬롯에 원자 저장되며 재시작·취소·Core 원장 outbox에서 재사용한다.
 
 ## `BrokerPort` Protocol 메서드 (BAT-056 / REQ-118)
@@ -461,7 +461,7 @@ get_current_price(symbol: str, market: str = "J") -> Optional[Decimal]
 ### KIS 어댑터 EXCG 명시화 (REQ-118)
 
 - `submit_order`: body에 `EXCG_ID_DVSN_CD: req.venue` 항상 명시 전송 (이전: 미전송·서버 기본값 의존 → 명시화로 견고성 향상). 실측(2026-07-06): NXT(EXCG=NXT) 주문 rt_cd=0 확인.
-- `AUTO` 세션: 08:00~08:49:59 NXT, 09:00:30~15:29:59 KRX, 15:30~20:00 NXT. 그 밖의 시간은 `auto_venue_session_closed`로 fail-closed 한다.
+- venue 누락은 `SOR`로 제출하며, 명시 KRX/NXT/SOR는 그대로 제출한다. core는 wall-clock으로 venue를 선택하지 않는다.
 - `cancel_order`: body에 `EXCG_ID_DVSN_CD: venue` 명시 전송. 실측(2026-07-06): NXT 취소 rt_cd=0 확인.
 - `poll_fill`: KIS 신형 일별주문체결조회 실전 `TTTC0081R`, 모의
   `VTTC0081R`을 사용하고 `EXCG_ID_DVSN_CD=ALL`을 전달한다. 일반 주문번호
diff --git a/docs/runtime-flows.md b/docs/runtime-flows.md
index 996e393..c06f575 100644
--- a/docs/runtime-flows.md
+++ b/docs/runtime-flows.md
@@ -264,7 +264,7 @@
 - 슬롯 `limit_price` 생애주기(dcy-012/REQ-002): INACTIVE→PENDING_BUY(매수 지정가 set) → PENDING_BUY→HOLDING(clear) → HOLDING→PENDING_SELL(매도 지정가 set 또는 None=시장가) → PENDING_SELL→INACTIVE(clear). 롤백(→INACTIVE) 전이에서도 clear. 외부 취소 후 holding 복귀에서도 clear 되어 재매도는 시장가.
 - **실행 정책 생애주기(dcy-022/REQ-068)**: `timeout_sec`·`slippage_pct` 는 `limit_price` 와 동일한 생애주기(PENDING_* 진입 시 set, HOLDING/INACTIVE 탈출 시 clear). 슬롯의 `updated_at` 이 dispatch 시각 proxy 로 사용된다(mark_dispatched 가 갱신, stale-alert 와 동일 방법).
 - 어댑터: paper(결정적 async 더블) / KIS(모의투자 검증, 실계좌 게이팅).
-- **venue 전달 경로(BAT-056/REQ-117/118, BAT-059/REQ-124, dcy-041)**: buy/sell intent `venue`(기본 AUTO) → pending `Slot.venue` → KIS 제출 시 KST 세션별 실제 KRX/NXT 확정 → `OrderAck.venue`와 주문번호 원자 저장 → 취소·재시작·Core outbox에서 실제 거래소 재사용. 허용값은 AUTO/KRX/NXT/SOR이며 invalid는 슬롯 전이 전 거부한다. HOLDING은 다음 자율매도를 위해 AUTO, INACTIVE는 하위 호환을 위해 KRX로 초기화한다.
+- **venue 전달 경로(BAT-056/REQ-117/118, BAT-059/REQ-124, dcy-041, GitHub #61)**: buy/sell intent `venue`(누락 시 SOR) → pending `Slot.venue` → KIS에 명시 KRX/NXT/SOR 제출 → `OrderAck.venue`와 주문번호 원자 저장 → 취소·재시작·Core outbox에서 실제 거래소 재사용. AUTO와 invalid 값은 슬롯 전이 전 거부한다. HOLDING은 다음 주문을 위해 SOR, INACTIVE는 하위 호환을 위해 KRX로 초기화한다.
 
 ### 계좌조회 단기 복구 (dcy-041 / GitHub #45)
 
diff --git a/tests/adapters/broker/test_venue.py b/tests/adapters/broker/test_venue.py
index c5d6701..84835e9 100644
--- a/tests/adapters/broker/test_venue.py
+++ b/tests/adapters/broker/test_venue.py
@@ -91,38 +91,28 @@ def test_order_request_venue_nxt():
     assert req.venue == "NXT"
 
 
-@pytest.mark.parametrize(
-    ("at", "expected"),
-    [
-        (datetime(2026, 7, 29, 8, 0, tzinfo=timezone(timedelta(hours=9))), "NXT"),
-        (datetime(2026, 7, 29, 8, 49, 59, tzinfo=timezone(timedelta(hours=9))), "NXT"),
-        (datetime(2026, 7, 29, 9, 0, 30, tzinfo=timezone(timedelta(hours=9))), "KRX"),
-        (datetime(2026, 7, 29, 15, 29, 59, tzinfo=timezone(timedelta(hours=9))), "KRX"),
-        (datetime(2026, 7, 29, 15, 30, tzinfo=timezone(timedelta(hours=9))), "NXT"),
-        (datetime(2026, 7, 29, 20, 0, tzinfo=timezone(timedelta(hours=9))), "NXT"),
-    ],
-)
-def test_auto_venue_resolves_by_kst_session(at, expected):
-    assert resolve_order_venue("AUTO", at) == expected
-
-
+@pytest.mark.parametrize("venue", ["KRX", "NXT", "SOR"])
 @pytest.mark.parametrize(
     "at",
     [
-        datetime(2026, 7, 29, 7, 59, 59, tzinfo=timezone(timedelta(hours=9))),
-        datetime(2026, 7, 29, 8, 50, tzinfo=timezone(timedelta(hours=9))),
-        datetime(2026, 7, 29, 9, 0, 29, tzinfo=timezone(timedelta(hours=9))),
+        datetime(2026, 7, 29, 8, 0, tzinfo=timezone(timedelta(hours=9))),
+        datetime(2026, 7, 29, 8, 55, tzinfo=timezone(timedelta(hours=9))),
         datetime(2026, 7, 29, 20, 0, 1, tzinfo=timezone(timedelta(hours=9))),
     ],
 )
-def test_auto_venue_fails_closed_outside_supported_sessions(at):
-    with pytest.raises(ValueError, match="auto_venue_session_closed"):
+def test_explicit_venue_is_preserved_independent_of_time(venue, at):
+    assert resolve_order_venue(venue, at) == venue
+
+
+def test_auto_venue_is_rejected():
+    at = datetime(2026, 7, 29, 8, 1, tzinfo=timezone(timedelta(hours=9)))
+    with pytest.raises(ValueError, match="unsupported_order_venue"):
         resolve_order_venue("AUTO", at)
 
 
-def test_submit_auto_uses_nxt_and_reports_actual_venue(monkeypatch):
+def test_submit_sor_preserves_sor(monkeypatch):
     captured = {}
-    at = datetime(2026, 7, 29, 8, 1, tzinfo=timezone(timedelta(hours=9)))
+    at = datetime(2026, 7, 29, 8, 55, tzinfo=timezone(timedelta(hours=9)))
 
     def fake_post(url, headers=None, json=None, timeout=None):
         captured["body"] = json
@@ -134,39 +124,17 @@ def test_submit_auto_uses_nxt_and_reports_actual_venue(monkeypatch):
     monkeypatch.setattr(kis_mod.httpx, "post", fake_post)
     ack = broker.submit_order(
         OrderRequest(
-            slot_id="s-auto",
+            slot_id="s-sor",
             side="buy",
             symbol="005930",
             qty=1,
-            venue="AUTO",
+            venue="SOR",
         )
     )
 
     assert ack.accepted is True
-    assert ack.venue == "NXT"
-    assert captured["body"]["EXCG_ID_DVSN_CD"] == "NXT"
-
-
-def test_submit_auto_outside_session_rejects_without_http(monkeypatch):
-    at = datetime(2026, 7, 29, 8, 55, tzinfo=timezone(timedelta(hours=9)))
-    broker = _mock_broker(clock=lambda: at)
-
-    def unexpected_post(*args, **kwargs):
-        raise AssertionError("AUTO session rejection must happen before HTTP")
-
-    monkeypatch.setattr(kis_mod.httpx, "post", unexpected_post)
-    ack = broker.submit_order(
-        OrderRequest(
-            slot_id="s-auto-closed",
-            side="buy",
-            symbol="005930",
-            qty=1,
-            venue="AUTO",
-        )
-    )
-
-    assert ack.accepted is False
-    assert ack.reason == "auto_venue_session_closed"
+    assert ack.venue == "SOR"
+    assert captured["body"]["EXCG_ID_DVSN_CD"] == "SOR"
 
 
 # ---------------------------------------------------------------------------
diff --git a/tests/adapters/persistence/test_migration_and_drift.py b/tests/adapters/persistence/test_migration_and_drift.py
index 703099b..1e25857 100644
--- a/tests/adapters/persistence/test_migration_and_drift.py
+++ b/tests/adapters/persistence/test_migration_and_drift.py
@@ -7,10 +7,11 @@ iteration: EXPECTED_SLOT_FIELDS (code contract) vs daily_slot actual columns
 from __future__ import annotations
 
 import psycopg
+import pytest
 
 from trex_core.adapters.persistence.migrate import apply_migrations, migration_files
 from trex_core.adapters.persistence.postgresql import PostgreSQLSlotRepository
-from trex_core.domain.slot import EXPECTED_SLOT_FIELDS, SlotService, SlotState
+from trex_core.domain.slot import EXPECTED_SLOT_FIELDS
 
 _EXPECTED_TABLES = {
     "daily_slot",
@@ -64,20 +65,29 @@ def test_apply_migrations_is_idempotent(pg_dsn):
     apply_migrations(pg_dsn)
 
 
-def test_migration_replay_accepts_existing_auto_venue_row(pg_clean):
+def test_migration_replay_converts_existing_auto_venue_row_to_sor(pg_clean):
     repo = PostgreSQLSlotRepository(pg_clean)
-    service = SlotService(repo, instance_key="migration-auto")
     repo.reconcile_universe("migration-auto", {"pf-auto": "005930"})
     slot = repo.find_slot_by_portfolio("migration-auto", "pf-auto")
-    service.transit_slot(
-        slot.slot_id,
-        SlotState.INACTIVE,
-        SlotState.PENDING_BUY,
-        reason="migration_replay",
-        actor="test",
-        venue="AUTO",
-    )
+    assert slot is not None
+
+    # Simulate a row written before migration 023 tightened the constraint.
+    with psycopg.connect(pg_clean) as conn:
+        with conn.cursor() as cur:
+            cur.execute("ALTER TABLE daily_slot DROP CONSTRAINT daily_slot_venue_check")
+            cur.execute(
+                "UPDATE daily_slot SET venue = 'AUTO' WHERE slot_id = %s",
+                (slot.slot_id,),
+            )
+        conn.commit()
 
     apply_migrations(pg_clean)
 
-    assert repo.fetch_slot(slot.slot_id).venue == "AUTO"
+    assert repo.fetch_slot(slot.slot_id).venue == "SOR"
+    with psycopg.connect(pg_clean) as conn:
+        with conn.cursor() as cur:
+            with pytest.raises(psycopg.errors.CheckViolation):
+                cur.execute(
+                    "UPDATE daily_slot SET venue = 'AUTO' WHERE slot_id = %s",
+                    (slot.slot_id,),
+                )
diff --git a/tests/application/test_execution_ledger.py b/tests/application/test_execution_ledger.py
index 476aff4..c641ed9 100644
--- a/tests/application/test_execution_ledger.py
+++ b/tests/application/test_execution_ledger.py
@@ -59,7 +59,7 @@ def test_buy_fill_enqueues_one_ledger_item_and_writer_records_it():
     assert (t.asset_id, t.side, t.qty, t.price) == ("PF-1", "buy", 10, 1000.0)
     assert t.execution_id.startswith("paper:PAPER-")
     assert t.fee > 0.0 and t.tax == 0.0
-    assert t.venue == "AUTO"
+    assert t.venue == "SOR"
 
 
 def test_sell_fill_enqueues_sell_ledger_item():
diff --git a/tests/application/test_execution_policy.py b/tests/application/test_execution_policy.py
index 17e3a04..14c4f84 100644
--- a/tests/application/test_execution_policy.py
+++ b/tests/application/test_execution_policy.py
@@ -253,6 +253,33 @@ class TestOrderResultLogging:
         assert all(r.levelno == logging.ERROR for r in rejects)
         assert "호가단위" in rejects[0].getMessage()
 
+    def test_sell_reject_returns_to_holding_without_new_attempt(self):
+        broker = _RecordingBroker()
+        repo, _, intents, execution = _wire(broker)
+        slot_id = _buy_to_pending(intents)
+        assert slot_id is not None
+        execution.run_once()
+        holding = repo.fetch_slot(slot_id)
+        assert holding is not None and holding.status is SlotState.HOLDING
+
+        intents.submit_sell(SellIntent(intent_id="s1", slot_id=slot_id))
+        broker.submit_order = lambda req: (
+            broker.orders.append(req)
+            or OrderAck(accepted=False, reason="broker_rejected", venue=req.venue)
+        )
+
+        result = execution.run_once()
+        recovered = repo.fetch_slot(slot_id)
+        assert recovered is not None
+        assert recovered.status is SlotState.HOLDING
+        assert recovered.qty == 10
+        assert recovered.broker_order_id is None
+        assert result.rolled_back == 1
+        assert len([order for order in broker.orders if order.side == "sell"]) == 1
+
+        execution.run_once()
+        assert len([order for order in broker.orders if order.side == "sell"]) == 1
+
     def test_normal_fill_emits_no_error(self, caplog):
         broker = _RecordingBroker()
         repo, svc, intents, execution = _wire(broker)
diff --git a/tests/application/test_sell_retryable_flag.py b/tests/application/test_sell_retryable_flag.py
index 39a2894..c6a8742 100644
--- a/tests/application/test_sell_retryable_flag.py
+++ b/tests/application/test_sell_retryable_flag.py
@@ -1,18 +1,12 @@
-"""rejected SellIntent `retryable` flag (issue #27 / REQ-007 CHG-20260615-01).
-
-Additive: only on intent_type="sell" + status="rejected". Maps reason→retryable
-via the core-owned table (unrecognized → True, safety default; bad_request → False).
-admitted / processing / buy responses must NOT carry the field.
-"""
+"""Strategy RPC responses never expose broker retryability (GitHub #60)."""
 from __future__ import annotations
 
+from uuid import uuid4
+
 from trex_core.adapters.persistence.in_memory_intent_store import InMemoryIntentStore
 from trex_core.application.intents import IntentService
 from trex_core.application.messaging import RpcRequest
-from trex_core.application.messaging_handlers import (
-    _sell_reject_retryable,
-    make_intent_rpc_handler,
-)
+from trex_core.application.messaging_handlers import make_intent_rpc_handler
 from trex_core.domain.slot import SlotService, SlotState
 from trex_core.domain.slot.in_memory_repository import InMemorySlotRepository
 
@@ -22,9 +16,14 @@ INST = "default"
 def _wire():
     repo = InMemorySlotRepository()
     svc = SlotService(repo, instance_key=INST)
-    intents = IntentService(svc, repo, InMemoryIntentStore(),
-                            resolve_symbol=lambda pid: "005930",
-                            instance_key=INST, max_active_slots=5)
+    intents = IntentService(
+        svc,
+        repo,
+        InMemoryIntentStore(),
+        resolve_symbol=lambda pid: "005930",
+        instance_key=INST,
+        max_active_slots=5,
+    )
     repo.reconcile_universe(INST, {"PF-1": "SYM"})
     handler = make_intent_rpc_handler(intents)
     slot = repo.list_slots(INST)[0]
@@ -32,72 +31,65 @@ def _wire():
 
 
 def _sell(handler, slot_id, intent_id="s1"):
-    return handler(RpcRequest(payload={
-        "intent_type": "sell", "intent_id": intent_id, "slot_id": str(slot_id),
-    }, correlation_id=intent_id))
+    return handler(
+        RpcRequest(
+            payload={
+                "intent_type": "sell",
+                "intent_id": intent_id,
+                "slot_id": str(slot_id),
+            },
+            correlation_id=intent_id,
+        )
+    )
 
 
-class TestRetryableMapping:
-    def test_each_reason_maps(self):
-        assert _sell_reject_retryable("slot_state_changed") is True
-        assert _sell_reject_retryable("slot_not_holding:pending_buy") is True
-        assert _sell_reject_retryable("duplicate_in_flight") is True
-        assert _sell_reject_retryable("slot_not_found") is False
-        assert _sell_reject_retryable("slot_not_holding:inactive") is False
-        assert _sell_reject_retryable("slot_not_holding:pending_sell") is False
-        assert _sell_reject_retryable("slot_not_holding:error") is False
-
-    def test_unrecognized_defaults_true(self):
-        assert _sell_reject_retryable("some_future_reason") is True
-        assert _sell_reject_retryable(None) is True
-
-    def test_bad_request_is_false(self):
-        assert _sell_reject_retryable("bad_request:KeyError('slot_id')") is False
+def test_rejected_sell_does_not_expose_retryability():
+    _, _, _, handler, slot = _wire()
+    response = _sell(handler, slot.slot_id)
+    assert response.payload["status"] == "rejected"
+    assert response.payload["reason"] == "slot_not_holding:inactive"
+    assert "retryable" not in response.payload
 
 
-class TestResponseField:
-    def test_rejected_sell_inactive_slot_has_retryable_false(self):
-        # slot is inactive (never bought) → slot_not_holding:inactive → terminal
-        repo, svc, intents, handler, slot = _wire()
-        resp = _sell(handler, slot.slot_id)
-        assert resp.payload["status"] == "rejected"
-        assert resp.payload["reason"] == "slot_not_holding:inactive"
-        assert resp.payload["retryable"] is False
+def test_unknown_slot_sell_does_not_expose_retryability():
+    _, _, _, handler, _ = _wire()
+    response = _sell(handler, uuid4())
+    assert response.payload["status"] == "rejected"
+    assert response.payload["reason"] == "slot_not_found"
+    assert "retryable" not in response.payload
 
-    def test_rejected_sell_unknown_slot_false(self):
-        from uuid import uuid4
-        _, _, _, handler, _ = _wire()
-        resp = _sell(handler, uuid4())
-        assert resp.payload["status"] == "rejected"
-        assert resp.payload["reason"] == "slot_not_found"
-        assert resp.payload["retryable"] is False
 
-    def test_bad_request_sell_carries_retryable_false(self):
-        _, _, _, handler, _ = _wire()
-        resp = handler(RpcRequest(payload={
-            "intent_type": "sell", "intent_id": "x",  # missing slot_id
-        }, correlation_id="x"))
-        assert resp.payload["status"] == "rejected"
-        assert resp.payload["reason"].startswith("bad_request")
-        assert resp.payload["retryable"] is False
+def test_malformed_sell_does_not_expose_retryability():
+    _, _, _, handler, _ = _wire()
+    response = handler(
+        RpcRequest(
+            payload={"intent_type": "sell", "intent_id": "x"},
+            correlation_id="x",
+        )
+    )
+    assert response.payload["status"] == "rejected"
+    assert response.payload["reason"].startswith("bad_request")
+    assert "retryable" not in response.payload
 
-    def test_admitted_sell_has_no_retryable(self):
-        repo, svc, intents, handler, slot = _wire()
-        # bring slot to holding so the sell is admitted
-        svc.transit_slot(slot.slot_id, SlotState.INACTIVE, SlotState.PENDING_BUY,
-                         reason="buy", actor="t")
-        svc.transit_slot(slot.slot_id, SlotState.PENDING_BUY, SlotState.HOLDING,
-                         reason="filled", actor="t", qty=10, avg_price=100)
-        resp = _sell(handler, slot.slot_id)
-        assert resp.payload["status"] == "admitted"
-        assert "retryable" not in resp.payload
 
-    def test_buy_rejection_has_no_retryable(self):
-        # buy on a non-existent slot → rejected, but buy responses omit retryable
-        from uuid import uuid4
-        _, _, _, handler, _ = _wire()
-        resp = handler(RpcRequest(payload={
-            "intent_type": "buy", "intent_id": "b1", "slot_id": str(uuid4()),
-        }, correlation_id="b1"))
-        assert resp.payload["status"] == "rejected"
-        assert "retryable" not in resp.payload
+def test_admitted_sell_does_not_expose_retryability():
+    _, svc, _, handler, slot = _wire()
+    svc.transit_slot(
+        slot.slot_id,
+        SlotState.INACTIVE,
+        SlotState.PENDING_BUY,
+        reason="buy",
+        actor="test",
+    )
+    svc.transit_slot(
+        slot.slot_id,
+        SlotState.PENDING_BUY,
+        SlotState.HOLDING,
+        reason="filled",
+        actor="test",
+        qty=10,
+        avg_price=100,
+    )
+    response = _sell(handler, slot.slot_id)
+    assert response.payload["status"] == "admitted"
+    assert "retryable" not in response.payload
diff --git a/tests/application/test_venue_intent_flow.py b/tests/application/test_venue_intent_flow.py
index aee5e22..b943e2a 100644
--- a/tests/application/test_venue_intent_flow.py
+++ b/tests/application/test_venue_intent_flow.py
@@ -3,6 +3,8 @@ from __future__ import annotations
 
 from uuid import UUID
 
+import pytest
+
 from trex_core.adapters.persistence.in_memory_intent_store import InMemoryIntentStore
 from trex_core.application.broker_port import (
     BalanceItem,
@@ -96,7 +98,8 @@ def test_nxt_buy_wire_value_reaches_broker_order() -> None:
     assert broker.orders[0].venue == "NXT"
 
 
-def test_invalid_venue_is_rejected_before_slot_transition() -> None:
+@pytest.mark.parametrize("invalid_venue", ["AUTO", "UNKNOWN"])
+def test_invalid_venue_is_rejected_before_slot_transition(invalid_venue: str) -> None:
     repo, intents, _, _ = _wire()
     handler = make_intent_rpc_handler(intents)
 
@@ -107,7 +110,7 @@ def test_invalid_venue_is_rejected_before_slot_transition() -> None:
                 "intent_id": "bad-venue",
                 "portfolio_id": "PF-1",
                 "qty": 1,
-                "venue": "UNKNOWN",
+                "venue": invalid_venue,
             },
             correlation_id="bad-venue",
         )
@@ -118,7 +121,7 @@ def test_invalid_venue_is_rejected_before_slot_transition() -> None:
     assert repo.list_slots("default")[0].status is SlotState.INACTIVE
 
 
-def test_omitted_wire_venue_is_auto_then_actual_venue_is_persisted() -> None:
+def test_omitted_wire_venue_is_sor_then_actual_venue_is_persisted() -> None:
     repo = InMemorySlotRepository()
     service = SlotService(repo)
     intents = IntentService(
@@ -146,10 +149,10 @@ def test_omitted_wire_venue_is_auto_then_actual_venue_is_persisted() -> None:
 
     slot_id = UUID(response.payload["slot_id"])
     pending = repo.fetch_slot(slot_id)
-    assert pending is not None and pending.venue == "AUTO"
+    assert pending is not None and pending.venue == "SOR"
     execution.run_once()
     dispatched = repo.fetch_slot(slot_id)
-    assert broker.orders[0].venue == "AUTO"
+    assert broker.orders[0].venue == "SOR"
     assert dispatched is not None and dispatched.venue == "NXT"
 
 
@@ -180,7 +183,7 @@ def test_inactive_transition_resets_venue_to_krx() -> None:
     assert reset.venue == "KRX"
 
 
-def test_holding_transition_resets_next_order_venue_to_auto() -> None:
+def test_holding_transition_resets_next_order_venue_to_sor() -> None:
     repo, intents, _, _ = _wire()
     decision = intents.submit_buy(
         BuyIntent(
@@ -201,7 +204,7 @@ def test_holding_transition_resets_next_order_venue_to_auto() -> None:
         qty=1,
         avg_price=1000,
     )
-    assert holding.venue == "AUTO"
+    assert holding.venue == "SOR"
 
 
 def test_operator_cancel_uses_original_nxt_venue() -> None:
diff --git a/trex_core/adapters/broker/kis.py b/trex_core/adapters/broker/kis.py
index 8ec1d5f..228cf5a 100644
--- a/trex_core/adapters/broker/kis.py
+++ b/trex_core/adapters/broker/kis.py
@@ -15,7 +15,7 @@ import base64
 import hashlib
 import json
 from dataclasses import replace
-from datetime import datetime, time, timedelta, timezone
+from datetime import datetime, timedelta, timezone
 from decimal import Decimal, InvalidOperation
 from time import monotonic
 from typing import Callable, Optional
@@ -40,7 +40,7 @@ _MOCK_HINTS = ("openapivts", "virtual", "mock")
 _FILL_POLL_MIN_INTERVAL_SECONDS = 5.0
 _FILL_POLL_TRANSPORT_BACKOFF_SECONDS = 30.0
 _SUBMISSION_LOOKUP_GRACE_SECONDS = 90.0
-_SUPPORTED_ORDER_VENUES = frozenset({"AUTO", "KRX", "NXT", "SOR"})
+_SUPPORTED_ORDER_VENUES = frozenset({"KRX", "NXT", "SOR"})
 
 
 def _balance_http_error_code(status: Optional[int]) -> str:
@@ -54,26 +54,15 @@ def _balance_http_error_code(status: Optional[int]) -> str:
 
 
 def resolve_order_venue(venue: str, at: datetime) -> str:
-    """Resolve AUTO to the venue that accepts domestic-stock orders at `at`.
+    """Validate and preserve an explicit KRX/NXT/SOR order venue.
 
-    The gaps are intentional fail-closed intervals. They prevent an AUTO order
-    from silently falling back to KRX while the opening venue is indeterminate.
-    Explicit KRX/NXT/SOR values are preserved.
+    ``at`` remains in the signature for compatibility with existing callers;
+    venue selection is deliberately independent of wall-clock time.
     """
     normalized = str(venue).strip().upper()
     if normalized not in _SUPPORTED_ORDER_VENUES:
         raise ValueError("unsupported_order_venue")
-    if normalized != "AUTO":
-        return normalized
-
-    current = at.astimezone(_KST).time().replace(tzinfo=None)
-    if time(8, 0) <= current < time(8, 50):
-        return "NXT"
-    if time(9, 0, 30) <= current < time(15, 30):
-        return "KRX"
-    if time(15, 30) <= current <= time(20, 0):
-        return "NXT"
-    raise ValueError("auto_venue_session_closed")
+    return normalized
 
 
 def _safe_int(v: object) -> Optional[int]:
diff --git a/trex_core/adapters/persistence/sql/023_remove_auto_order_venue.sql b/trex_core/adapters/persistence/sql/023_remove_auto_order_venue.sql
new file mode 100644
index 0000000..45f06ef
--- /dev/null
+++ b/trex_core/adapters/persistence/sql/023_remove_auto_order_venue.sql
@@ -0,0 +1,16 @@
+-- GitHub #61: remove Core-owned wall-clock AUTO routing.
+-- Existing durable AUTO values are normalized before the stricter constraints.
+UPDATE daily_slot SET venue = 'SOR' WHERE venue = 'AUTO';
+UPDATE ledger_outbox SET venue = 'SOR' WHERE venue = 'AUTO';
+
+ALTER TABLE daily_slot
+    DROP CONSTRAINT IF EXISTS daily_slot_venue_check;
+ALTER TABLE daily_slot
+    ADD CONSTRAINT daily_slot_venue_check
+    CHECK (venue IN ('KRX', 'NXT', 'SOR'));
+
+ALTER TABLE ledger_outbox
+    DROP CONSTRAINT IF EXISTS ledger_outbox_venue_check;
+ALTER TABLE ledger_outbox
+    ADD CONSTRAINT ledger_outbox_venue_check
+    CHECK (venue IN ('KRX', 'NXT', 'SOR'));
diff --git a/trex_core/application/broker_port.py b/trex_core/application/broker_port.py
index afb16a0..6ab70e4 100644
--- a/trex_core/application/broker_port.py
+++ b/trex_core/application/broker_port.py
@@ -71,9 +71,8 @@ class OrderAck:
     accepted: bool
     broker_order_id: Optional[str] = None
     reason: Optional[str] = None
-    # Actual venue used for submission. KIS resolves AUTO before the HTTP call;
-    # execution persists this value with the broker order id so restart/cancel
-    # never has to infer the original venue.
+    # Actual venue used for submission. Execution persists this value with the
+    # broker order id so restart/cancel never has to infer the original venue.
     venue: Optional[str] = None
     raw: dict[str, Any] = field(default_factory=dict)
     submitted_at: Optional[datetime] = None
diff --git a/trex_core/application/intents.py b/trex_core/application/intents.py
index d0f05cb..aeafa19 100644
--- a/trex_core/application/intents.py
+++ b/trex_core/application/intents.py
@@ -77,9 +77,8 @@ class BuyIntent:
     # slippage_pct: effective limit = entry_price*(1+pct/100) buy / *(1-pct/100) sell.
     timeout_sec: Optional[int] = None
     slippage_pct: Optional[float] = None
-    # Strategy wire default. AUTO is resolved at the broker boundary so
-    # strategies remain session-agnostic while explicit KRX/NXT/SOR is kept.
-    venue: str = "AUTO"
+    # Missing strategy venue uses KIS SOR; explicit KRX/NXT/SOR is preserved.
+    venue: str = "SOR"
     extra: dict[str, Any] = field(default_factory=dict)
 
 
@@ -98,7 +97,7 @@ class SellIntent:
     # dcy-022 / REQ-068: execution policy (optional, backward-compat).
     timeout_sec: Optional[int] = None
     slippage_pct: Optional[float] = None
-    venue: str = "AUTO"
+    venue: str = "SOR"
     extra: dict[str, Any] = field(default_factory=dict)
 
 
@@ -229,7 +228,7 @@ class IntentService:
         timeout_error = self._timeout_error(intent.timeout_sec)
         if timeout_error is not None:
             return IntentDecision(intent.intent_id, "rejected", None, timeout_error)
-        if intent.venue not in {"AUTO", "KRX", "NXT", "SOR"}:
+        if intent.venue not in {"KRX", "NXT", "SOR"}:
             return IntentDecision(intent.intent_id, "rejected", None, "invalid_venue")
 
         # dcy-036 / REQ-114: day-start entry gate (fail-closed).
@@ -347,7 +346,7 @@ class IntentService:
         timeout_error = self._timeout_error(intent.timeout_sec)
         if timeout_error is not None:
             return IntentDecision(intent.intent_id, "rejected", None, timeout_error)
-        if intent.venue not in {"AUTO", "KRX", "NXT", "SOR"}:
+        if intent.venue not in {"KRX", "NXT", "SOR"}:
             return IntentDecision(intent.intent_id, "rejected", None, "invalid_venue")
 
         slot = self._repo.fetch_slot(intent.slot_id)
diff --git a/trex_core/application/messaging_handlers.py b/trex_core/application/messaging_handlers.py
index 525bc78..8e0add9 100644
--- a/trex_core/application/messaging_handlers.py
+++ b/trex_core/application/messaging_handlers.py
@@ -30,32 +30,6 @@ from trex_core.domain.slot import (
 _log = logging.getLogger(__name__)
 
 
-# ---- sell-reject retryability (issue #27 / REQ-007 CHG-20260615-01) ---------
-# core-owned reason -> retryable mapping for the rejected SellIntent response.
-# Maintained with the reject vocabulary (intents.py _admit_sell/_dedup) so a new
-# reason gets a correct flag without the daemon touching a table. Unrecognized
-# reasons default to retryable=True: a stranded stop-loss (held losing position)
-# is worse than bounded, observable hammering on a terminal decision.
-_SELL_REJECT_RETRYABLE: dict[str, bool] = {
-    "slot_state_changed": True,
-    "slot_not_holding:pending_buy": True,
-    "duplicate_in_flight": True,
-    "slot_not_found": False,
-    "slot_not_holding:inactive": False,
-    "slot_not_holding:pending_sell": False,
-    "slot_not_holding:error": False,
-}
-
-
-def _sell_reject_retryable(reason: Optional[str]) -> bool:
-    """Map a rejected-sell reason to retryable (issue #27). Default True (safety)."""
-    if reason is None:
-        return True
-    # malformed payload: client defect — retrying the same bytes is pointless.
-    if reason.startswith("bad_request"):
-        return False
-    return _SELL_REJECT_RETRYABLE.get(reason, True)
-
 
 # ---- intent RPC handler -----------------------------------------------------
 
@@ -117,7 +91,7 @@ def make_intent_rpc_handler(
                     # dcy-022 / REQ-068: execution policy (optional, backward-compat).
                     timeout_sec=_opt_int(body.get("timeout_sec")),
                     slippage_pct=_opt_float(body.get("slippage_pct")),
-                    venue=_opt_str(body.get("venue")) or "AUTO",
+                    venue=_opt_str(body.get("venue")) or "SOR",
                 )
                 d = intent_service.submit_buy(buy)
             elif intent_type == "sell":
@@ -133,7 +107,7 @@ def make_intent_rpc_handler(
                     # dcy-022 / REQ-068: execution policy (optional, backward-compat).
                     timeout_sec=_opt_int(body.get("timeout_sec")),
                     slippage_pct=_opt_float(body.get("slippage_pct")),
-                    venue=_opt_str(body.get("venue")) or "AUTO",
+                    venue=_opt_str(body.get("venue")) or "SOR",
                 )
                 d = intent_service.submit_sell(sell)
             else:
@@ -146,9 +120,6 @@ def make_intent_rpc_handler(
                 "intent_id": intent_id, "status": "rejected",
                 "slot_id": None, "reason": f"bad_request:{exc}",
             }
-            # issue #27: sell-side malformed payload carries retryable=False.
-            if intent_type == "sell":
-                payload["retryable"] = _sell_reject_retryable(payload["reason"])
             return RpcResponse(payload=payload)
         payload = {
             "intent_id": d.intent_id,
@@ -156,9 +127,6 @@ def make_intent_rpc_handler(
             "slot_id": (str(d.slot_id) if d.slot_id else None),
             "reason": d.reason,
         }
-        # issue #27 / REQ-007 AC-7: additive retryable on rejected sell only.
-        if intent_type == "sell" and d.status == "rejected":
-            payload["retryable"] = _sell_reject_retryable(d.reason)
         return RpcResponse(payload=payload)
 
     return handler
diff --git a/trex_core/domain/slot/service.py b/trex_core/domain/slot/service.py
index db3f892..d86e30f 100644
--- a/trex_core/domain/slot/service.py
+++ b/trex_core/domain/slot/service.py
@@ -232,9 +232,8 @@ class SlotService:
             new_timeout_sec = None
             new_slippage_pct = None
             # A completed order's venue must not leak into a later autonomous
-            # sell. The next order starts session-aware unless its intent
-            # explicitly chooses KRX/NXT/SOR.
-            new_venue = "AUTO" if to_state is SlotState.HOLDING else slot.venue
+            # sell. Missing venue defaults to KIS SOR for the next order.
+            new_venue = "SOR" if to_state is SlotState.HOLDING else slot.venue
 
         # occupancy_seq (dcy-028/REQ-081): bump when a slot begins a new
         # occupancy (inactive→pending_buy). Stable across the rest of the