We already have AD FS 2.0 running for our Office 365 environment, but I was just tasked with configuring AD FS 3.0 on separate servers for an upgrade. Somehow I'm supposed to stand these servers up with AD FS 3.0, and then get SSO to work for everyone like it did with 2.0 with everyone being none the wiser. There is documentation everywhere for brand new AD FS 3.0 installs, in-place upgrades from 2.0, but there is nothing (that I've found) for this unique situation.
Has anyone encountered this before? I was just about to import my exported config from 2.0 into my 3.0 servers, but then I realized that I have no idea what the implications of that are if both environments are up and running at the same time. Thanks a million in advance if you can provide guidance for a lost soul.