Apple TV 4 users can still restore back to tvOS 10.2.2 and jailbreak with greeng0blin. Any Apple TV 4 can move to the right firmware to use it, regardless of their current setup, but you’ll need to think carefully before you do.
1) Download the Apple TV 4 tvOS 10.2.2 IPSW file. (google it)
2) Ensure that tvOS 10.2.2 is still signed before starting. Otherwise, your restore will fail and you will have to upgrade to the current firmware.
3) Connect your Apple TV 4 to your computer and open iTunes.
4) Hold down the shift key (Windows), or the option/alt key (Mac), and then click the Restore Apple TV… button.
The next step will wipe your device, and all your saved info and settings. It will have to be set up again as new.
5) A file browser will appear. Navigate to the tvOS 10.2.2 IPSW firmware file which you downloaded and select it.
6) Accept the prompts to restore, and wait until it completes before disconnecting your computer.
For more in-depth instructions, check read full article here.