iOS 13.3.1 (build 17D5050a) is an official Apple over-the-air update for the iPhone 7 (Global), released on 2020-01-22T18:07:31Z. The update package is 170.22 MB. This is a delta (partial) update that requires 13.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2289b2223d691280e48461b482d007949225789e.zip.