watchOS 5.3.6 (build 16U662) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm), released on 2020-03-24T17:21:26Z. The update package is 55.54 MB. This is a delta (partial) update that requires 5.3.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: b1904e191f89a76ba9b4759cf660c5b468529598.zip.