With these companies now saying do not upgrade the OS I fully understand why PG Music has said nothing about BiaB Mac 2019. It will be interesting to see if any other type of software companies come out with similar announcements.
MacBook Pro 2020 - Big Sur 11.2.3
BiaB UltraPak+ 2020 Mac, (423)
Yamaha SLG200N
Epiphone Les Paul Studio

Logic Pro X,
Xtra Styles 1 - 10. Loops-with-Style PAK 1 & 2. Multistyles PAK 1.