iOS 9.9.10.3.1 (build 14E304) is an official Apple over-the-air update for the iPhone 6s, released on 2017-04-03T17:00:34Z. The update package is 1.15 GB. This is a delta (partial) update that requires 9.3.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9137269ec909036d669cc18c22a6ef52a44bf398.zip.