Suggestion on automatic removal on permissions/delegates

Hi! I just wanted to make a suggestion that from time to time, we come across that if a user is removed from Exchange, the removed user stays in Calendar/Delegate for some other user. If that removed user was set to receive meeting copies, then anyone emails the "some other user" will receive a bounce for the removed user. Any chance it could be added where if Outlook detects that a user doesn't exist in Exchange anymore, then removed user is automatically removed from Calendar/Delegate permissions?