Outlook 2016 has a profile creation changes we know about. Specifically, manual profile creation for an Exchange mailbox is no longer available. You must use Auto Discover to create the profile. All previous versions of Outlook using Auto Discover (2007, 2010, and 2013) had manual profile creation as an option if Auto Discover failed. There seems to be another change we weren’t told about.
As the rule base generated by AADConnect has gotten larger and larger and a simple configuration setting change can generate multiple rules, it has become a challenge to keep track of what is going on. So when the configuration changes or there is a version upgrade, how does one tell what changed? This is not as important in a “standard” configuration but if the “standard” rules are changed by disabling rules, copying and modifying rules, or adding new rules, it is important to be aware how an upgrade handles those modifications.