Apple initially stopped signing several older iOS versions for specific iPhone and iPad models, preventing users from restoring or downgrading to those software releases. This move affected devices such as the iPhone 5c, iPhone 5, iPhone 4S, and various iPad 2 and iPad mini models, impacting versions like iOS 10.3.3, 9.3.6, and 6.1.3.

These signing restrictions typically prevent users from installing older, potentially less secure, software. For users maintaining older devices for testing, app compatibility, or archival purposes, this closure of restore paths presented a challenge. However, Apple has since resumed signing these iOS versions, allowing owners of the affected legacy devices to restore to the specified software once more.

The devices impacted included the iPhone 5c (iOS 10.3.3), iPhone 5 (iOS 10.3.3/10.3.4), iPad mini (iOS 9.3.5/9.3.6), and iPad 2 (iOS 9.3.5/9.3.6), among others. While Apple usually stops signing newer versions after security updates, it occasionally restricts older builds for legacy hardware.

This situation ultimately allows users with older iPhones and iPads to continue using their devices with the latest compatible software for those models, preventing involuntary upgrades or loss of access to specific operating system versions.