Thanks. I don't think the unenroll procedures are working.
I wasn't actually enrolled in the Beta scheme but I too had this problem (for another reason).
I can tell you what I did but you may not like it
First I tried to re-install using the "re-install macOS" option in the recovery environment but that only offered me Big Sur Beta. This was on a brand new, out of the box M1 MBP. You could try that first but I suspect you'll find it offers the Beta.
I didn't want that so to cut a long story short I downloaded 11.1 from the App store and made a USB installer from it (after 2 failed downloads) and re-installed 11.1 from that using the second procedure in the link below (from "Or follow these steps").
That completely solved my problems with Beta seeds.
https://support.apple.com/en-us/HT211983
Mine said beta too, when I started the process. I'd imagine it may still say that if I boot to recovery.
I am indeed on the release, as I double clicked to see my build number after I went through all of that.
It's not hurting anything, I'm just a bit OCD about badges. I may just turn that off until 11.2 comes out.
I do worry about the trackpad. Apple actually fixed one trackpad issue for me that was introduced in Big Sur's Beta, which was on my 16" Intel. When using multiple desktops, if you were in a browser and tried to three finger swipe to another desktop, it read that as two fingers and would take the browser back instead.
It was the first time they got back with me in a beta for more information and then followed up when the build came out that fixed it to make sure it was fine.
They have the best trackpads in the game. It scares me that they are introducing problems to them.
As a sidenote... You didn't run into the account creation bug when you used the USB? Every time I restored from the recovery, my M1 would hang at account creation and you could never get past it or login. It would even think the iCloud password was wrong (this is well documented on the web).
Ultimately, I took a TM backup from my old 16" and used it to 'migrate' my user account. That is the only thing that got me back into the system.
I did terminal commands, resets of passwords, but every single install after a format resulted in the inability to fully create a user account.
So I installed the 11.1 RC 2 yesterday and it was running fine until this morning the Mail app decided it would no longer open up. I tried everything to fix it and resorted to formatting the drive and reinstalling 11.1 RC 2 clean. Everything went find until I got to the part where you create a...
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