Earlier quoted context omitted.
Yes. You can access Outlook365 and Exchange via APIs as well as Google Apps for Business. Plus Calendars, etc. Anything that uses LDAP locally and now through the 365 APIs.
How does it work, an outlook 365 admin(?) Can read anyone's email that they want? Do they essentially just log onto the normal Hi as that user?
So there must be a way to assign ownership of a mailbox to another user.