Thanks to Derek for this comment:
“I updated on an original mini 16 and a 3 16.
Audiobus still works – as do the smattering of synth apps I’ve tried so far. Animoog -> Echo Pad -> Cubase via Audiobus for example.
Update takes a while better part of 20 mins.
About 150MB less memory afterwards – did a double sync before to get a baseline.”
Anyone else have any impressions?