iOS 13.3.1 (build 17D5026c) is an official Apple over-the-air update for the iPhone 8 (Global), released on 2019-12-17T18:13:21Z. The update package is 287.44 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: 486a8bd10b54c39906c5a3a41f38cbbc875a0bc0.zip.