[WARN] Tried connecting to router ... identity keys were not as expected

Background: Tor Browser 12.0, Tor 4.7.12, Windows 7, vanilla bridges.

Repeatedly getting the following log line.

[WARN] Tried connecting to router at *address* ID=<none> RSA_ID=*FP1*, but RSA + ed25519 identity keys were not as expected: wanted *FP1* + no ed25519 key but got *FP2* + *edFP*.

Ideas of what happened:

MITM
Bridge operator reinstalled it in-between me getting the bridge and now.

What is wrong:

Bridge should be marked as unreachable: either it is not used already and connections are doomed to spend resources for nothing, or it should not be used as something is clearly wrong with it
There should be a way to distinguish first idea from second - my best guess is building a tunneled directory connection to bridge authority and asking "Is there a bridge FP2 and does it listen on address?"

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information