iOS 12.1.1 (build 16C5050a) is an official Apple over-the-air update for the iPhone 6s, released on 2018-11-15T18:04:59Z. The update package is 300.2 MB. This is a delta (partial) update that requires 12.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 79aebc0a62d046310f5263d5c05536dcfdf64c92.zip.