iPhone 6S on iOS 15 Compatible | Upgrade & Downgrade Full Guide - YouTube
How to Downgrade iOS 15.6.1 to iOS 15.6 on iPhone and iPad
How to Downgrade iOS 14.2 to iOS 14.1 on iPhone, iPad [Tutorial]
iPhone 6s Plus teardown reveals a 165 mAh battery downgrade versus last year's iPhone 6 Plus
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Discussion] Successfully downgraded iPhone 6 to iOS 11.4! Big thanks to u/DoggoFox123 aka Mineek (sunst0rm tool). I am open for any questions! : r/jailbreak
NEW* Untethered Downgrade iPhone SE/6S/6S Plus iOS 13 to iOS 12 No Losing Data (Windows User) - YouTube
Considering an iOS 10 downgrade? Here are a few things to keep in mind - 9to5Mac