watchOS 6.1 (build 17S5076a) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2019-10-16T17:13:59Z. The update package is 370.57 MB. This is a delta (partial) update that requires 6.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 87e7a2d9bec2ab0427573d97bd9dabe963046a83.zip.