watchOS 6.0 (build 17R5575a) is an official Apple over-the-air update for the Apple Watch Series 4 (40mm), released on 2019-08-27T17:31:14Z. The update package is 682.89 MB. This is a delta (partial) update that requires 5.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ed4602f5132545b4f14aee52b675e7bf784b5ed4.zip.