Users can update who will be receiving their complimentary tickets up until the ticket window closes from the Department -> Complimentary Tickets, My Requests tab.
Once there, click on the Request button.
If you requested tickets and want to add another guest, you should add the new guest to a Guest # slot that does not have an existing guest listed and hit save.
If you are replacing an existing guest, you will want to add the new guest to one of the occupied Guest # fields and hit save.