watchOS 6.0 (build 17R5575a) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2019-08-27T17:31:27Z. The update package is 688.07 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: 02ab2e3cf7fd197ddfe5e69082eb024c82d8c24d.zip.