watchOS 6.0 (build 17R5571a) is an official Apple over-the-air update for the Apple Watch Series 4 (40mm, LTE), released on 2019-08-21T17:12:07Z. The update package is 74.36 MB. This is a delta (partial) update that requires 6.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ca0c3250461567d28a6e2a976a588ff1bf95c748.zip.