watchOS 6.0 (build 17R5571a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2019-08-21T17:10:56Z. The update package is 737.23 MB. This is a delta (partial) update that requires 5.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: bc503d8a2885590d84ca285711045c73bd3cbfbd.zip.