When deleting certain types of data that trigger automatic user group changes, the change log entries are not removed. This can cause other automatic user group changes that try to add one of the "orphaned" change entry groups to fail. Primarily, this would manifest itself when a promotion was deleted and the groups were manually removed from promoted users. If another promotion (or user upgrade) was triggered on the same groups, those users would not receive the promotion. This is fixed for 1.1.4, but not fixed retroactively. Orphaned data may still cause issues.