iOS 9.9.11.4 (build 15F79) is an official Apple over-the-air update for the iPhone 6s, released on 2018-05-29T17:16:21Z. The update package is 1.48 GB. This is a delta (partial) update that requires 9.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5c4d7a4ef7205c7f6e1fd1bbfef28b00b1121bb8.zip.