iOS 13.3.1 (build 17D5026c) is an official Apple over-the-air update for the iPhone 7 (GSM), released on 2019-12-17T18:13:36Z. The update package is 261.88 MB. This is a delta (partial) update that requires 13.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a873c62767edec2bc9e8b529cbf64e106d932aca.zip.