You know how those tin-foil-hat types are…
If it can be changed to “enhance” security, then by golly! Let’s do it! The problem, of course, is the rule of unintended consequences. You know, what happens to something else because of action A, that is totally unplanned, and no one knows about it.
And, while I am mentioning it… have you ever noticed that the same team YOU have to run everything through for approval never asks your team if it is OK if they make a change? They just do it? Odd how that works out, eh?
It turns out that about 6 weeks ago, the aforementioned team instituted a change to the default AD containers. To whit, they changed the default computer container to be something other than the OOBE.
Turns out that breaks SfB big time. As in no more publishing the topology. A Get-CsAdDomain fails. But that is the clue to the fix.
Simply run the SfB Domain prep again.