tvOS 12.1.2 (build 16K534) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2019-01-22T18:13:42Z. The update package is 984.49 MB. This is a delta (partial) update that requires 10.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f28379173126bb6c9514cf9e026e1112ab36359e.zip.