I have two Exchange accounts registered in Outlook, one for Company A (e.g. my employer) and one for Company B (e.g. my client's firm - I'm a consultant). If I am trying to schedule a meeting with people from both organizations, I should be able to see everyone's free/busy data in the Scheduling Assistant view, not just the ones in the organization of the account that is sending the meeting invite.
In 2016CU1 an ability to define amount of items returned in search for the user has been removed.
The following change, as outlined in https://support.microsoft.com/en-us/kb/3093866 (target env. Exchange 2013)
worked for Exchange 2016 RTM.