watchOS 4.2.2 (build 15S6542) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2018-01-19T18:09:20Z. The update package is 54.36 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: e44df8c39186869ed8e142d04adc17b092fe3954.zip.