tvOS 12.3 (build 16M5117f) is an official Apple over-the-air update for the Apple TV 4K, released on 2019-03-27T17:14:28Z. The update package is 1.57 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c3129f7ff3778834adc98ec70597da195c9cee88.zip.