tvOS 12.2.1 (build 16L250) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2019-04-10T17:06:55Z. The update package is 396.36 MB. This is a delta (partial) update that requires 12.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 4026a91211a311fd2f7373ee2b30b3ec0f7b3585.zip.