tvOS 14.0 (build 18J386) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2020-09-16T20:14:27Z. The update package is 1.09 GB. This is a delta (partial) update that requires 13.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f827d4822d9647c7a17db396e95a1f0044f670a2.zip.