watchOS 6.1 (build 17S5054e) is an official Apple over-the-air update for the Apple Watch Series 1 (42mm), released on 2019-09-23T17:03:59Z. The update package is 690.19 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: 7c32e39af894162876a33a11d1ca365495600927.zip.