UPDATE 2/12/21
The Exchange Sustained Engineering Team continued servicing all customer issues for Exchange 2016 that were opened with Microsoft by the end of Mainstream Support, which was Oct 13, ...
Updated Feb 12, 2021
Version 12.0
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Greg Taylor - EXCHANGE thanks for the clarification, I assumed it was something to do with the long-term roadmap of moving to the cloud.
To give a little more context to the SME environment, we are looking at moving our own server infrastructure to be cloud based (lead by example) and have done most of it such as placing all our shared files on OneDrive or Sharepoint, and have MS365 for Office Apps and email. The next step in our plan is to remove on-prem Exchange, but for that we need to make our user accounts cloud based, and not synced via Azure AD Connect. Simple enough in itself to break the sync and recover the user from Deleted Users, but our on-prem ADDS is used to sync all sorts of other SSO integrations, such as LDAP to our MFA solution (WatchGuard AuthPoint) our RMM platform, client documentation platform, etc. It very quickly opens a can of worms to say "make the users cloud based", as I expect is the case with most SME's - certainly is with most of our clients with ADDS. Having in-cloud user accounts will also allow us to use that account to register new devices such as laptops during initial setup and login as the MS365/Azure account, instead of having to join the laptop to on-prem active directory, with all the associated remote working/VPN complications that brings.
We are now turning our attention to Azure ADDS (which it seems is different to the rather badly named "Azure AD"), so will see how that goes.
All of that means, for now, that we still have to rely on Exchange for MS365 tenants with Azure AD Connect, and are very keen to get to a point where on-prem Exchange with all the additional hardware and support costs, is no longer a requirement.
Best,
Kevin