iOS 9.9.10.3.1 (build 14E304) is an official Apple over-the-air update for the iPhone 6, released on 2017-04-03T17:00:32Z. The update package is 1.5 GB. This is a delta (partial) update that requires 8.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ddc204004c6d556590881d4cdefd9eafa3d767d3.zip.