The Cupertino Boys All versions after iOS 11.2.5 have stopped signing, a week after the final version was released. Specifically, Apple has stopped signing iOS 11.2, iOS 11.2.1 and iOS 11.2.2 for all the devices that today were compatible with these versions of iOS.
Apple regularly stops signing older versions, every time you release a new version of the mobile operating system, in an effort so that all users can enjoy all the updates that have been introduced, not only improving the stability of the system, but also protecting against threats that continually reach the Internet.
By stopping signing the previous versions, Apple ensures that users they cannot go back and expose themselves to risks and security problems. Until yesterday, it was possible to install both iOS 11.2 and iOS 11.2.1 and iOS 11.2.2, since the Cupertino servers continued to sign them, but for a few hours, it is no longer possible and if you try to downgrade to these versions or earlier , the device will never be updated and will think forever while waiting to receive a confirmation that will never arrive from Apple's servers.
Jailbreak users, or the possible jailbreak that has been rumored for a few weeks for iOS 11.2.1 yes they will be affected, if as of today they still had not made the corresponding downgrade waiting for the opportunity to install the jailbreak, if it finally reaches the market, since at present it is impossible to do so after Apple has stopped signing that version.
iOS 11.2.5 hit the market in its final version last week with several new features around Siri, offering official support for the HomePod, the new Apple device that will begin to reach the first users from February 9, in addition to solving and solving various performance problems, something common in all versions of iOS that Apple launches.
The thing about updates improving stability is a huge lie. With each update the system worsens its performance. IOS 11 has rendered my 1st gen iPad Air, which was working great, obsolete. Now I have a new Air, with IOS 10 and I don't dare to update.