iOS 8.4.1 Jailbreak
If you're still on the iPhone 6 Plus iOS 8.4.1 update, be on the look out for the iOS 8.4.1 jailbreak this month. There's a chance developers will release it ahead of the iOS 9.1 release.
If you've already moved to the iOS 9 update, you're stuck. There is no way back to iOS 8 so you're have to keep your eyes peeled for an iOS 9 jailbreak.
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