diff --git a/cli/main.py b/cli/main.py
index 6752d61..a8ae0cb 100644
--- a/cli/main.py
+++ b/cli/main.py
@@ -6,7 +6,7 @@ Uses core.models for all data access, never raw SQL.
 import json
 import os
 import sys
-from datetime import datetime
+from datetime import datetime, timezone
 from pathlib import Path
 
 import click
@@ -618,13 +618,13 @@ def run_task(ctx, task_id, dry_run, allow_write):
 
     # Step 1: PM decomposes
     click.echo("Running PM to decompose task...")
-    pm_started_at = datetime.utcnow().isoformat()
+    pm_started_at = datetime.now(timezone.utc).isoformat()
     pm_result = run_agent(
         conn, "pm", task_id, project_id,
         model="sonnet", dry_run=dry_run,
         allow_write=allow_write, noninteractive=is_noninteractive,
     )
-    pm_ended_at = datetime.utcnow().isoformat()
+    pm_ended_at = datetime.now(timezone.utc).isoformat()
 
     if dry_run:
         click.echo("\n--- PM Prompt (dry-run) ---")
diff --git a/tests/test_api.py b/tests/test_api.py
index 081824a..1107d71 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -2342,3 +2342,102 @@ def test_get_pipeline_logs_since_id_returns_pm_entries(client):
     done_log = next(log for log in logs if "PM done" in log["message"])
     assert done_log["extra_json"]["steps_count"] == 2
     assert done_log["extra_json"]["tokens_used"] == 1000
+
+
+# ---------------------------------------------------------------------------
+# KIN-103 — PATCH /api/projects/{id} — worktrees_enabled toggle
+# ---------------------------------------------------------------------------
+
+def test_patch_project_worktrees_enabled_true(client):
+    """PATCH с worktrees_enabled=true → 200, поле установлено в 1."""
+    r = client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    assert r.status_code == 200
+    assert r.json()["worktrees_enabled"] == 1
+
+
+def test_patch_project_worktrees_enabled_false(client):
+    """После включения PATCH с worktrees_enabled=false → 200, поле установлено в 0."""
+    client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    r = client.patch("/api/projects/p1", json={"worktrees_enabled": False})
+    assert r.status_code == 200
+    assert r.json()["worktrees_enabled"] == 0
+
+
+def test_patch_project_worktrees_enabled_true_persisted_via_sql(client):
+    """После PATCH worktrees_enabled=True прямой SQL подтверждает значение 1."""
+    client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+
+    from core.db import init_db
+    conn = init_db(api_module.DB_PATH)
+    row = conn.execute("SELECT worktrees_enabled FROM projects WHERE id = 'p1'").fetchone()
+    conn.close()
+    assert row is not None
+    assert row[0] == 1
+
+
+def test_patch_project_worktrees_enabled_false_persisted_via_sql(client):
+    """После PATCH worktrees_enabled=False прямой SQL подтверждает значение 0."""
+    client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    client.patch("/api/projects/p1", json={"worktrees_enabled": False})
+
+    from core.db import init_db
+    conn = init_db(api_module.DB_PATH)
+    row = conn.execute("SELECT worktrees_enabled FROM projects WHERE id = 'p1'").fetchone()
+    conn.close()
+    assert row is not None
+    assert row[0] == 0
+
+
+def test_patch_project_worktrees_enabled_null_before_first_update(client):
+    """Новый проект имеет worktrees_enabled=0 (DEFAULT) до первого обновления."""
+    client.post("/api/projects", json={"id": "p_new", "name": "New", "path": "/new"})
+
+    from core.db import init_db
+    conn = init_db(api_module.DB_PATH)
+    row = conn.execute("SELECT worktrees_enabled FROM projects WHERE id = 'p_new'").fetchone()
+    conn.close()
+    assert row is not None
+    assert not row[0]  # DEFAULT 0 или NULL — в любом случае falsy
+
+
+def test_patch_project_worktrees_enabled_get_includes_field(client):
+    """GET проекта включает worktrees_enabled в ответе."""
+    r = client.get("/api/projects/p1")
+    assert r.status_code == 200
+    data = r.json()
+    assert "worktrees_enabled" in data
+
+
+def test_patch_project_worktrees_enabled_and_autocommit_together(client):
+    """PATCH с worktrees_enabled и autocommit_enabled → оба поля обновлены."""
+    r = client.patch("/api/projects/p1", json={
+        "worktrees_enabled": True,
+        "autocommit_enabled": True,
+    })
+    assert r.status_code == 200
+    data = r.json()
+    assert data["worktrees_enabled"] == 1
+    assert data["autocommit_enabled"] == 1
+
+
+def test_patch_project_worktrees_enabled_no_change_when_not_in_patch(client):
+    """PATCH без worktrees_enabled → поле не меняется."""
+    # Сначала установим worktrees_enabled=1
+    client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    # Потом патч без worktrees_enabled не должен его менять
+    r = client.patch("/api/projects/p1", json={"autocommit_enabled": True})
+    assert r.status_code == 200
+    assert r.json()["worktrees_enabled"] == 1
+
+
+def test_patch_project_worktrees_enabled_toggle_sequence(client):
+    """Последовательные включение/выключение worktrees_enabled."""
+    # Включаем
+    r1 = client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    assert r1.json()["worktrees_enabled"] == 1
+    # Отключаем
+    r2 = client.patch("/api/projects/p1", json={"worktrees_enabled": False})
+    assert r2.json()["worktrees_enabled"] == 0
+    # Снова включаем
+    r3 = client.patch("/api/projects/p1", json={"worktrees_enabled": True})
+    assert r3.json()["worktrees_enabled"] == 1
diff --git a/tests/test_kin_104_regression.py b/tests/test_kin_104_regression.py
new file mode 100644
index 0000000..81fe9e1
--- /dev/null
+++ b/tests/test_kin_104_regression.py
@@ -0,0 +1,53 @@
+"""Regression tests for KIN-104 — замена datetime.utcnow() на datetime.now(timezone.utc) в cli/main.py.
+
+AC1: datetime.utcnow() отсутствует в cli/main.py.
+AC2: timezone импортирован из datetime в cli/main.py.
+AC3: datetime.now(timezone.utc).isoformat() возвращает строку с суффиксом +00:00 (aware datetime).
+"""
+
+import re
+from datetime import datetime, timezone
+from pathlib import Path
+
+import pytest
+
+
+CLI_MAIN = Path(__file__).parent.parent / "cli" / "main.py"
+
+
+# ---------------------------------------------------------------------------
+# AC1: utcnow() отсутствует в источнике
+# ---------------------------------------------------------------------------
+
+def test_cli_main_does_not_contain_utcnow():
+    """cli/main.py не должен содержать вызовов datetime.utcnow()."""
+    source = CLI_MAIN.read_text(encoding="utf-8")
+    assert "utcnow" not in source, "Найден устаревший вызов utcnow() в cli/main.py"
+
+
+# ---------------------------------------------------------------------------
+# AC2: timezone импортирован
+# ---------------------------------------------------------------------------
+
+def test_cli_main_imports_timezone():
+    """cli/main.py должен импортировать timezone из datetime."""
+    source = CLI_MAIN.read_text(encoding="utf-8")
+    # Принимаем: from datetime import datetime, timezone  или  from datetime import ..., timezone, ...
+    assert re.search(r"from datetime import [^#\n]*timezone", source), \
+        "timezone не импортирован из datetime в cli/main.py"
+
+
+# ---------------------------------------------------------------------------
+# AC3: aware datetime → isoformat содержит +00:00
+# ---------------------------------------------------------------------------
+
+def test_now_timezone_utc_isoformat_contains_utc_offset():
+    """datetime.now(timezone.utc).isoformat() должен содержать '+00:00'."""
+    ts = datetime.now(timezone.utc).isoformat()
+    assert "+00:00" in ts, f"Ожидался суффикс +00:00, получено: {ts}"
+
+
+def test_now_timezone_utc_is_aware():
+    """datetime.now(timezone.utc) должен возвращать aware datetime (tzinfo не None)."""
+    dt = datetime.now(timezone.utc)
+    assert dt.tzinfo is not None, "datetime.now(timezone.utc) вернул naive datetime"