iOS 9.9.10.3.1 (build 14E304) is an official Apple over-the-air update for the iPhone 6s+, released on 2017-04-03T17:00:35Z. The update package is 1.35 GB. This is a delta (partial) update that requires 9.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5f0eff06fdbb1afe6925e068434368175ac370fa.zip.