watchOS 4.3.1 (build 15T567) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2018-05-29T17:08:55Z. The update package is 333.26 MB. This is a delta (partial) update that requires 4.2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2d08e8cd8a28295f8321c2a8805595ec3a6d2924.zip.