iOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 7 Plus (GSM), released on 2017-12-13T18:15:05Z. The update package is 592.45 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ca3b25a128670a662453d8a0b201c16ead6f972f.zip.