You Can't Downgrade to iOS 8 or iOS 9.0
You can no longer downgrade the iPhone 5 to iOS 8 or iOS 9.0. Apple stopped signing on these updates and if you move to iOS 9.0.2 you're stuck with iOS 9.0.2 or iOS 9.0.1.
You can still downgrade to the iOS 9.0.1 update but Apple will probably only keep that open for a few more days before closing it off. The company won't announce when it plans to do this so you'll want to keep an eye out in the days ahead.
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