tvOS 13.3.1 (build 17K795) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2020-01-28T18:42:31Z. The update package is 845.22 MB. This is a delta (partial) update that requires 12.4.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 7f3f8f421ad080de92cbe90a711a09004633a0ad.zip.