diff --git a/backend/app/models/watched_repo.py b/backend/app/models/watched_repo.py
index 0930f29..a99ac48 100644
--- a/backend/app/models/watched_repo.py
+++ b/backend/app/models/watched_repo.py
@@ -91,3 +91,20 @@ def delete(watched_id: str) -> bool:
             .execute()
         )
         return len(result.data) > 0
+
+    @staticmethod
+    def delete_by_agent(agent_id: str) -> None:
+        """Remove every watched_repos row for an agent.
+
+        Called by Orchestrator.stop_agent so an offboarded agent stops
+        occupying its (user, owner, repo) slot — otherwise the cross-agent
+        uniqueness from #28 would block re-hiring against the same repo
+        (#31). Fire-and-forget: we don't care about the row count.
+        """
+        (
+            get_supabase()
+            .table(TABLE)
+            .delete()
+            .eq("agent_id", agent_id)
+            .execute()
+        )
diff --git a/backend/app/services/orchestrator.py b/backend/app/services/orchestrator.py
index 5998aee..e081a45 100644
--- a/backend/app/services/orchestrator.py
+++ b/backend/app/services/orchestrator.py
@@ -5,6 +5,7 @@
 from docker.errors import NotFound, APIError
 from app.config import get_settings
 from app.models.agent import AgentModel
+from app.models.watched_repo import WatchedRepoModel
 from app.services.template_loader import load_template
 
 
@@ -95,6 +96,11 @@ def stop_agent(self, agent_id: str) -> dict | None:
             except NotFound:
                 pass
 
+        # Release the agent's repo subscriptions so a re-hire under the same
+        # user can take the same (owner, repo) — #31. agent_memory /
+        # agent_action_log / reviewed_prs are preserved as the audit trail.
+        WatchedRepoModel.delete_by_agent(agent_id)
+
         # Clear the token: a stopped agent must not authenticate.
         AgentModel.update(
             agent_id, status="stopped", container_id=None, agent_token=None
diff --git a/backend/tests/test_orchestrator.py b/backend/tests/test_orchestrator.py
index 3c20e20..c02ad93 100644
--- a/backend/tests/test_orchestrator.py
+++ b/backend/tests/test_orchestrator.py
@@ -223,6 +223,34 @@ def test_stop_agent_not_found(self, fake_supabase, mock_docker):
         result = orch.stop_agent("nonexistent")
         assert result is None
 
+    def test_stop_agent_releases_watched_repos(self, fake_supabase, mock_docker):
+        """Offboarding must release the agent's repo subscriptions so a
+        re-hire under the same user can take the same (owner, repo) — #31.
+        Audit tables (agent_memory / agent_action_log / reviewed_prs) are
+        intentionally untouched."""
+        from app.services.orchestrator import Orchestrator
+
+        agent = {
+            "id": "agent-001",
+            "user_id": "user-001",
+            "role": "code-review-engineer",
+            "container_id": "ctr-123",
+            "status": "running",
+            "config_json": {},
+        }
+        agents_table = fake_supabase.get_table("agents")
+        agents_table.set_select_result([agent])
+        agents_table.set_update_result([{**agent, "status": "stopped"}])
+        mock_docker.containers.get.return_value = MagicMock()
+
+        with patch(
+            "app.services.orchestrator.WatchedRepoModel.delete_by_agent"
+        ) as mock_delete:
+            orch = Orchestrator()
+            orch.stop_agent("agent-001")
+
+        mock_delete.assert_called_once_with("agent-001")
+
 
 class TestGetAgentStatus:
     def test_clears_agent_token_when_container_exited(self, fake_supabase, mock_docker):