Following the release of iOS 13.4 on March 24, Apple has stopped signing iOS 13.3.1, which means downgrading to that version of iOS is no longer possible.
Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date.
Developers can also download iOS 13.4.5, an upcoming update with bug fixes and a new option to share Apple Music songs on Instagram Stories.
This article, “Apple Stops Signing iOS 13.3.1 Following Release of iOS 13.4” first appeared on MacRumors.com
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