ATLAS Scheduler Global and Calendar Permissions
User01 is a Global Request Viewer. User01 is also an Owner on Calendar01. If Calendar01 is made private, User01 will still be able to view it and make changes. If User01 was only a Global Request Viewer, she/he would not be able to view Calendar01 if it was private.
Below are two graphs detailing the permissions associated with the different users of Scheduler.