After the public release of iOS 15.4.1 users can no longer downgrade to iOS 15.4 through official channels.
Apple has stopped signing iOS 15.4.1, which was launched in March this year. The Cupertino-based company does this on a regular basis as a way to get users to update their devices to the latest version.
iOS 15.4 introduced several notable features, such as iPad Universal Control, new emojis and the ability to unlock iPhones without having to remove face masks.
In the meantime, iOS 15.4.1 came out with a battery drain issue fix for affected iPhones, as well as plugging a bug within AppleAVD to prevent it from being exploited. Apple says that there may be individuals who are trying to use this bug and recommends to have it updated to iOS 15.4.1 as soon as possible.
In similar news, Apple has also stopped signing HomePod 15.4 and tvOS 15.4.