watchOS 6.1 (build 17S5083a) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2019-10-23T17:11:06Z. The update package is 779.2 MB. This is a delta (partial) update that requires 5.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f39f01f4fa2ec4508252c0b33b6bfcb8bf349cf8.zip.