iOS 13.4 (build 17E5223h) is an official Apple over-the-air update for the iPhone 8 Plus (GSM), released on 2020-02-05T18:17:26Z. The update package is 803.13 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: a514e91a8c3042007b51e6e55698b750a9b65944.zip.