iOS 9.2.1 (build 13D15) is an official Apple over-the-air update for the iPhone 6+, released on 2016-01-19T17:59:53Z. The update package is 1.32 GB. This is a delta (partial) update that requires 8.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d58eba362c1e6ce07ec7ed46bd1c9580ea6e7aec.zip.