8th Great (nest) Migration - December 1?

It will be interesting to see if locations as well as contents change this time round.

The only mass spawning nest I've found locally is currently throwing out Vulpix - can't be much less useful whatever it turns into :)

This seems like something they'd be likely to do. They seem to like to have nest migrations after the end of an event, maybe to make things more interesting even though an event just ended.

Your prediction is right. Today, I find two parks near my place have been changed, one from Duduo to Omastar nest and one from Squirtle to Jynx nest. I caught at least 4 Omastars and met 5 Jynx (caught 2 only) this morning.