iOS 11.1 (build 15B93) is an official Apple over-the-air update for the iPhone 6s+, released on 2017-10-23T17:07:54Z. The update package is 1.2 GB. This is a delta (partial) update that requires 10.3.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5985476c77635663b9a0cb2aa045375245c48417.zip.