iOS 9.9.10.3.1 (build 14E304) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2017-04-03T17:00:27Z. The update package is 1.48 GB. This is a delta (partial) update that requires 8.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 697781eefe4769f59bf430a8fce0ff402253b6f4.zip.