iPadOS 12.1.1 (build 16C50) is an official Apple over-the-air update for the iPad Air (China), released on 2018-12-05T18:07:22Z. The update package is 261.15 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: bd9467fd637f86287d1e1537073189bcee1e15f1.zip.