watchOS 6.0 (build 17R5566a) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2019-08-15T17:18:43Z. The update package is 687.39 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: 6dafa43654512e716835cb21f665d9557b9e9031.zip.