We're seeing retired client records getting a more recent update than their retired date though the systems are offline. This appears to cause problems with App Management licensing.
The Inventory Clean Up task deletes inventory data for computers that are no longer in use from the Notification Database; these are computers with a status of Retired, Disposed, or Returned to Lessor.
The task does insert records into the ResourceUpdateSummary table when these deletions are made.
This has been confirmed by development to be working as designed and is not the problem with App Mgmt's license usage.