iOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 7 Plus (Global), released on 2017-12-13T18:14:48Z. The update package is 397.27 MB. This is a delta (partial) update that requires 11.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 07c351888ec84c6c0a19b94b65bf0c3eb4e3b54b.zip.