diff --git a/test_runner/regress/test_timeline_size.py b/test_runner/regress/test_timeline_size.py
index a338b76511..19c29de44b 100644
--- a/test_runner/regress/test_timeline_size.py
+++ b/test_runner/regress/test_timeline_size.py
@@ -300,7 +300,8 @@ def test_timeline_initial_logical_size_calculation_cancellation(
     env = neon_env_builder.init_start()
     client = env.pageserver.http_client()
 
-    tenant_id, timeline_id = env.neon_cli.create_tenant()
+    tenant_id = env.initial_tenant
+    timeline_id = env.initial_timeline
 
     # load in some data
     endpoint = env.endpoints.create_start("main", tenant_id=tenant_id)