watchOS 6.0 (build 17R5556d) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2019-08-07T17:14:04Z. The update package is 738.17 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: 05de2cfb3bb3a102578d80fc17626d763204c153.zip.