Following the launch of iOS 16.1.2 on November 30, Apple has stopped signing iOS 16.1.1 and iOS 16.1, two previously available versions of iOS. With iOS 16.1 and iOS 16.1.1 no longer being signed, it is not possible to downgrade to those versions of iOS after upgrading to iOS 16.1.2.

Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date, so it is not unusual that the updates are no longer being signed.

iOS 16.1 was a major update that added support for iCloud Photo Library and Live Activities, while iOS 16.1.1 was a bug fix update.

iOS 16.1.2 will soon be replaced with iOS 16.2, a major update that is in testing and should launch next week. iOS 16.2 will introduce Advanced Data Protection for iCloud, the Freeform app, Apple Music Sing, and other new features.

Source: Macrumors