Apple stops signing iOS 15.0.2, killing downgrades from iOS 15.1 just one week after launch

Apple last Monday released iOS & iPadOS 15.1 to the general public following a lengthy beta testing period with a bevy of enhancements for the company’s mobile operating systems. Those enhancements comprised of SharePlay, support for COVID-19 vaccination cards in the Wallet app, an automatic macro toggle for the Camera app, and a plethora of bug fixes among other things.

Downgrade iOS 15

But as many of us come to expect after witnessing a software update from Apple, the company just this evening closed the signing window for the previous version of iOS & iPadOS, which in this case was version 15.0.2.

When Apple stops signing a particular version of iOS or iPadOS as they’ve done tonight, it means that the company has instructed its software update servers to reject user restore requests for that version. In other words, attempting to restore your device to an unsigned version of iOS or iPadOS via your Mac or Windows PC will instead prompt you to restore and update to the latest version.

Unofficial workarounds that take advantage of .shsh2 blobs and third-party software can be articulated by iPhone or iPad users who truly want to downgrade to a specific, unsigned version of iOS or iPadOS, but this method requires a substantial amount of additional effort and having pre-saved said .shsh2 blobs before the firmware in question became unsigned.

Jailbreakers are most frequent for using the method above, as jailbreak tools often only support older and unsigned firmware since Apple continuously launches software updates incorporating bug fixes and security improvements that patch the vulnerabilities used by jailbreak developers to poke holes in Apple’s mobile operating systems.

But jailbreaks aside, ordinary iPhone and iPad users will also sometimes see themselves downgrading to an older version of iOS or iPadOS, especially in the case of Apple introducing a major software bug with one of their updates that hinders the expected functionality of the device or other connected devices. While it may sound unheard of, several examples of this exist in recent history, including:

When software bugs like those listed above transpire, a software downgrade can provide temporary refuge until Apple is able to address the problem in yet another software update.

While we, and many other iPhone and iPad users wish that Apple wouldn’t unsign older firmware, Apple’s rationale is that it wants users to take advantage of the latest new features, security patches, and bug fixes. Obviously, it also pleases the company’s shareholders when Apple touts significant new firmware adoption, whether those numbers are artificially inflated by the software unsigning process or not.

If you ever find yourself wondering what version(s) of iOS or iPadOS are being signed for your device, then you may find IPSW.me online utility to be incredibly useful for your needs. Of course, you can also visit our dedicated Downloads page to acquire any firmware version for your device that you might be searching for.

Are you sad to see that iOS & iPadOS 15.0.2 are no longer being signed? Be sure to let us know your thoughts on the matter in the comments section down below.