Apple just this evening stopped signing iOS and iPadOS 15.1.1 (for the iPhone 12 and 13 lineups) and iOS and iPadOS 15.1 for all the rest of the company’s mobile devices after releasing iOS and iPadOS 15.2 just last week.
The Cupertino-based Apple regularly stops signing older firmware shortly following the release of a software update because doing so prevents its users from downgrading or restoring to the older firmware and avoiding what the company considers to be important software updates.
Downgrades are most common among jailbreakers who wish to run older firmware that are more susceptible to exploits. While this is the chief reason why Apple prevents software downgrades, other reasons include corralling as many users as possible onto newer versions to promote security in addition to pleasing shareholders.
Albeit uncommon, even non-jailbreakers sometimes downgrade their firmware after an update to a newer version when the update breaks a feature considered to be important to that user or introduces troublesome bugs.
While it was once possible to downgrade firmware using .shsh2 blobs and third-party software regardless of the firmware’s signing status, that all changed starting with iOS and iPadOS 14.8.1, as Apple appears to have changed how the downgrading and restoring system works with respect to newer firmware versions. Older firmware can still be restored or downgraded to, however, assuming the user has the necessary resources.
Since no jailbreaks currently exist for any version of iOS and iPadOS 15, today’s news isn’t all that frustrating for avid jailbreakers-to-be. On the other hand, those hoping to jailbreak iOS or iPadOS 15 are strongly advised to stay on the lowest possible firmware to enhance their odds of being able to jailbreak in the future.
As always, you can monitor which version(s) of iOS or iPadOS are being signed for your device(s) on the handy IPSW.me website. You can also download individual firmware file(s) for your device(s) from our dedicated downloads page.
Are you upset that Apple has stopped signing iOS and iPadOS versions 15.1 and 15.1.1? Be sure to tell us why or why not in the comments section down below.