watchOS 6.0 (build 17R5521e) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2019-07-02T18:10:50Z. The update package is 665.92 MB. This is a delta (partial) update that requires 5.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2e37995d162f0194673186e81bedd916136ed539.zip.