https://wccftech.com/macos-big-sur-11-1-beta-now-available-for-registered-developers/

If you are a registered developer then you can go ahead and download macOS Big Sur 11.1 beta 1 right now on your Mac.

Apple had a pretty eventful day today in the Mac side of the garden. Not only the new M1 computers from the company went on sale but we were hit with initial reviews as well. But in all that noise Apple released the first ever beta of macOS Big Sur 11.1.