tvOS 12.1 (build 16J602) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2018-10-30T17:14:33Z. The update package is 819.98 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1b1c803a32e8286726e4bf4f3003357bf9baa642.zip.