iOS 11.1.1 (build 15B150) is an official Apple over-the-air update for the iPhone 6s, released on 2017-11-09T18:10:56Z. The update package is 40.55 MB. This is a delta (partial) update that requires 11.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2fac23484476dadf108516031e2a6787979aa455.zip.