(EDIT March 24, 2021, we have a NEW UPDATE about Big Sur. Click Here to read this information that is newer than what is posted below).
If you already own an ALFA 802.11ac USB WiFi booster and have followed our steps to get it to work on Mac OS 10.15 Catalina, you may be wondering if you upgrade to Big Sur (released by Apple today, November 12th), if your product will still work after the update. Operating system upgrades can often times break hardware.
The good news is we have tested it today and can confirm with the 11.0.1 release the ALFA AWUS036AC and AWUS036ACH still work well.
We have not yet confirmed if you can do a new install the same way you can on Catalina. So if you do not yet own an ALFA AWUS036ACH and are looking to get one and install it on Big Sur, we have not yet confirmed the installer will work. We should have an update on that in the next few days and will post to our blog.
Military and First Responder 
Jan 23, 2021 wireless adaptor AWUS036ACH the problem is still compatibility. it does not work with big sur
Any news for the AWUS036ACH or AWUS1900 for MacOS Big Sur? What’s about the ALFA team? I did not contacted them, but they should have a solution.
Hi,
I have MacOS 11.1 running but I cannot get the AWUS036ACH to run. When will you have a driver available?
So is there any view on when these drivers will be available?
Ok, then what is the timeline on Big Sur compatibility? Right now your products are bricks for new installations of macs.