https://wccftech.com/download-ios-12-beta-12-with-fix-for-false-ios-update-prompt/

It was previously reported that iOS 12 beta users were seeing a false update prompts on their iPhone and iPad. The message informed users that a new iOS update is available and they should update from iOS 12 beta. However, no new iOS update was available which was quite annoying. In fact, users saw the prompt every time they unlocked their iPhone. Now, the company has released iOS 12 beta 12 which fixes the false iOS update prompt. Let’s see some more details on it.

As we have mentioned earlier, Apple has released iOS 12 beta 12 to developers which carries the fix to the false iOS update prompt. if you’re interested, you can download the beta 12 on your iPhone and iPad right now from the Apple Developer Center. Do make sure that a proper configuration profile is required.