watchOS 6.1 (build 17S5083a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2019-10-23T17:10:53Z. The update package is 775.96 MB. This is a delta (partial) update that requires 5.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 65ebe2754a7fa4ae2817edc2f54f4bcde0772734.zip.