iOS 11.4 (build 15F5079a) is an official Apple over-the-air update for the iPhone 8 Plus (Global), released on 2018-05-17T17:02:20Z. The update package is 324.83 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: bf986b39136c40f2bccdb8736a1025f15ccd58c4.zip.