iPhone 6 Plus Downgrade Options
The iPhone 6 Plus can still run iOS 8.4.1 and iOS 9 thanks to the option to downgrade.
Apple normally removes this feature after a short period, so this will not likely last long. While this is open you can try our iOS 9.0.1 and then go back to iOS 9 or even back to iOS 8.4.1 if you have problems.
Before you start this process, make sure that Apple is still signing the update you want to downgrade to. If Apple is no longer signing, you cannot downgrade. When you are ready, use this guide to go back to iOS 8.4.1 or iOS 9.
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