iOS 12.1 (build 16B92) is an official Apple over-the-air update for the iPhone 6s, released on 2018-10-30T17:16:57Z. The update package is 1.7 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: 292ea06138b79a451e0b6c422631575e82027ce3.zip.