N/A
The removal of users without ALL CASE access, is by design. If an older case is being restored, security concerns are addressed by not restoring old and possibly no longer employees of the company, access to the restored case. If the user has ALL CASE access, they will be granted access to the restored case.
Users that do not have ALL CASE access will be removed from access to the case being restored. As of version V9.1.2 and V9.2, the job status log will report the users that are dropped from case access.