tvOS 12.0.1 (build 16J380) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2018-09-24T17:13:26Z. The update package is 879.1 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2809b22a21430cee58a91303427614f9fca2f638.zip.