So the (lone) server in a very small (2 person) office was activated with an evaluation key and configured (very extensively) - awaiting budget for the license. Only to find out that it must be demoted from DC and another machine take on the role just to enter a license.
So, effectively, stuck. Seems nuts given there surely must be literally millions of single server small offices. But here we are.
Please no "did you do your homework/RTFM" slams. That's why I'm asking: this did not come up in anything I did do.