iOS 11.1.1 (build 15B150) is an official Apple over-the-air update for the iPhone 6s, released on 2017-11-09T18:10:46Z. The update package is 1.16 GB. This is a delta (partial) update that requires 10.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 18bce53facee874c40c8bbf474307364ec5d19bf.zip.