Alert popping up: "A new iOS update is now available. Please update from the iOS 14 beta"

Same problem here on IpadOS14.2 started yesterday (saw the issue early on in the V14 beta but it went away after a day). Now happens fairly often while the ipad is running and for sure each time it boots.

Tried deleting + reinstalling the beta profile with no luck.
Deleting the profile will not revert back to the non-beta version (why not, another problem???)

Suggestion: Please log it via the Feedback Application on your devices as well. I logged it this morning.

Very annoying indeed. Especially when it’s apparently not easily correctable. Beta software ... c’est la vie.

If you haven’t done so already, create a bug in Apple’s feedback app to report the problem.

I'm guessing that the iOS 14.2 beta 4 build has an incorrect expiration date, and we have passed it. This can probably only be fixed by a new build with correct date. So everyone put in a Feedback request and maybe the gods of Apple will notice it.

temporary solution, put in manual, the time and date, put the day a week ago ... and wait for the apple solution

I went through a wipe and clean install of iOS 14 beta 4 (18b5083a) from the .ipsw and the same problem occurs.

found a now unnecessary workaround ...
I downgraded my iPhone XI to the public iOS 14.1 (18a84395) using the .ipsw here on developer.apple.com and [understandably] I stopped getting not getting the, "Please update from the iOS 14 beta" alert dialog anymore. I restored from the .ipsw using Catalina via the standard device window built-into the Finder. For safety sake I did a full back up iCloud *and* a full local backup from the device. Specific iPhone XI model, A2160 MW9G2LL/A. Had previously been on iOS 14.2 beta 4. Restore from .ipsw completed without any problems.

Alas, after going through all this today, I then discovered that Apple released a release candidate of iOS 14.2 today (10/30) that fixes the iOS 14 beta update dialog. So if you haven't already, check for updates and/or manually update to iOS 14.2 release candidate (18B91).