Hello @EnterpriseArchitect
Based on the document link that you have shared, I assumed that you have WID database. I would suggest you to install secondary ADFS Server on Windows Server 2016, in the same farm. Once the installation is done, you can use below command to make the new server as Primary ADFS Server:
Set-AdfsSyncProperties -Role PrimaryComputer
And convert the old ADFS Server to secondary by using below command:
Set-AdfsSyncProperties -Role SecondaryComputer -PrimaryComputerName {FQDN}
You can then point a few computers to the new ADFS Server by making Host file entries and test if everything is working fine with the new server. Once confirmed, you can decommission the old server and assign the same IP address to the new ADFS Server. Also, raise the farm level, so that you can use the new features available with ADFS 2016.
I don't see any impact of rolling back the VM snapshot If there is no WID replication or WAP servers are there. Rollback may impact WID replication and secure channel with WAP servers. So if you plan to ever roll back, make sure you have only one ADFS Server in place.
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