After releasing iOS 15.2.1 in early January, Apple officially stopped signing iOS 15.2 today. With iOS 15.2 no longer signed, if you’ve already updated to iOS 15.2.1, it’s not possible to downgrade to that version. Apple typically stops signing software updates for older versions after new versions come out, to encourage customers to keep their operating systems up to date.
Released on December 13, iOS 15.2 includes several notable improvements to Apple’s mobile software, including app privacy reporting, SOS, traditional contacts, a new Apple Music voice plan, and more. The subsequent release of iOS 15.2.1 fixed an issue that prevented messages sent via iCloud links from loading, and it also fixed a bug that caused third-party CarPlay apps not to respond to input.