iOS 9.2.1 (build 13D14) is an official Apple over-the-air update for the iPhone 6, released on 2016-01-04T17:58:50Z. The update package is 33.6 MB. This is a delta (partial) update that requires 9.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 778ea14ffcabf3ee152c8b446c3b6a96e501440d.zip.