iOS 9.9.11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 6, released on 2017-12-13T18:12:59Z. The update package is 1.29 GB. This is a delta (partial) update that requires 9.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 07a193191ea16922ada3f46b124c02e1fcbcb917.zip.