Apple halts iOS 13.6 code signing following iOS 13.6.1 release
Apple on Wednesday stopped signing code for iOS 13.6, effectively preventing users who updated to the latest iOS 13.6.1 release from downgrading.
Issued last week, iOS 13.6.1 includes a handful of bug fixes including a patch for a thermal management issue that would in some cases cause an iPhone's screen to display a green tint.
The release also remedied a problem with Exposure Notification alerts and an issue that prevented the deletion of unused system files.
Today's code signing stoppage means users can no longer download the out-of-date iOS 13.6 operating system from Apple's servers. Apple regularly ceases signing of older code to prevent installation of past iOS versions following the release of a new version in a bid to keep users safe from new threats. The practice also ensures devices are running the latest feature-rich software.