iOS 12.1.2 (build 16C101) is an official Apple over-the-air update for the iPhone XS Max (China), released on 2018-12-17T21:06:20Z. The update package is 494.2 MB. This is a delta (partial) update that requires 12.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c5ece443f865842d709df42389c984fc8a49121b.zip.