FYI, just completed my upgrade from 10.15.7 to Big Sur 11.0.1. Process was seamless. Did take a me a little longer than an hour. I’m running a bunch of SoftRaid disks and those required an upgrade to a SoftRaid 6 public beta, which was simple and took just a few minutes. Looking forward to putting the dual Vega IIs through their paces per @imag4media’s experience. Flame 2021.1 wouldn’t launch, as expected, but a fresh install of 2021.2 was refreshing as there was no need to temporarily disable csrutil.
Also, I can’t remember if this is new or not, but, the ability to copy an older Flame project and create a new one for 2021.2 or convert an older project into a newer version, was quick and painless. Didn’t need to recreate the framestore.