Apple has ceased signing of code older than iOS 13.1, following this week’s release of iOS 13.1.2, which patched a small number of issues on the iPhone.
Apple stopped signing iOS 12.4.1, iOS 13.0, and iOS 13.1.1 last Friday, but continued signing iOS 13.1 until Monday.
Today’s cease to signing iOS 13.1 code comes on the heels of the Cupertino firm’s release of the iOS 13.1.2 update to close a security hole that granted third-party keyboards “full access” to iOS assets without user approval.
This is a routine move by Apple who commonly ceases signing older versions of their operating systems in an effort to encourage users to keep their devices’ operating systems up to date.