Usage delivery after project deletion

Deleting a project no longer blocks queued usage from other projects on the same Engine or TURN server.

Usage is delivered asynchronously. A queued batch can contain data for a project that has since been deleted alongside data for active projects. Delivery now respects the deleted project's lifecycle while recording the remaining usage exactly once, including when delivery is retried.

Deleted project history is not recreated. Existing usage retention and workspace boundaries remain unchanged.

See Observability for the usage data model and retention periods.