Apple Just Stopped Signing iOS 15.0.1, Downgrade from iOS 15.0.2 No Longer Possible
Apple has just stopped signing iOS 15.0.1 and iPadOS 15.0.1 updates for iPhone and iPad devices around the globe.
You Can No Longer Downgrade to iOS 15.0.1 or iPadOS 15.0.1 as Apple has Stopped Signing the Firmware
What this means is pretty straightforward, if you were thinking about jumping straight to that firmware, or downgrading from iOS 15.0.2 or iPadOS 15.0.2, then you can no longer do that.
Once the signing window is closed by Apple, the option of restoring to that firmware completely goes away. So, what should you do at this point? Simple, stick with what’s already installed, if that’s what you want, or jump straight to iOS 15.0.2 or iPadOS 15.0.2.
Keep one thing in mind as well; if you are planning to downgrade from the latest iOS 15.1 or iPadOS 15.1 RC builds, you have to choose iOS 15.0.2 or iPadOS 15.0.2 and download the correct IPSW files accordingly.
iOS 15.1 and iPadOS 15.1 is apparently set for release next week alongside macOS Monterey.
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