iOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPhone 7 Plus (Global), released on 2018-04-24T17:11:28Z. The update package is 855.01 MB. This is a delta (partial) update that requires 11.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f1214c7e828495f0ed96b40c068e57b29d7acc9f.zip.