watchOS 6.1 (build 17S5054e) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm), released on 2019-09-23T17:04:45Z. The update package is 254.39 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: d9d3b16de8fa7ca47c2bf233616201337c66c1d5.zip.