iOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 8 Plus (GSM), released on 2017-12-13T18:11:03Z. The update package is 399.84 MB. This is a delta (partial) update that requires 11.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a1cd667644a67dee020b6a5dbec64f3bac1058ca.zip.