I currently have a 2010 Exchange environment which has a working 2010 hybrid for several years. It is working between the 10,000 Office 365 users and approx. the same on-prem. The problem we always have had it Shared Mailboxes and accessing them which requires the users to be on-prem Exchange.
The company I work for has made the decision to start migrating all users to Office 365, or as many as we can. The question I have is, is there a benefit of having Exchange 2013 Hybrid to allow the smooth transition of the Shared Mailboxes with keeping the 2010 Mailbox/CAS Servers? Is there much of a benefit in doing this or would we be better off skipping that portion.
The goal is to make it as transparent as possible to the users. I already know we are going to lose delegates and some permissions which we accept.
What would others suggest?