iOS 13.3.1 (build 17D5044a) is an official Apple over-the-air update for the iPhone 8 (Global), released on 2020-01-14T18:20:59Z. The update package is 282.44 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: 5e99387dbbbf6c0d1e5d52e0576ca31b8e041482.zip.