iOS 12.1.2 (build 16C101) is an official Apple over-the-air update for the iPhone 6s, released on 2018-12-17T21:06:59Z. The update package is 1.29 GB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 8063128677644c81970dea24c69e98a609cb7d1b.zip.