watchOS 5.2 (build 16T5222a) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2019-03-11T17:12:04Z. The update package is 157.14 MB. This is a delta (partial) update that requires 5.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f7128b1471ec81d166b053aaa8ca7f0450a1c721.zip.