iPadOS 12.1 (build 16B5059d) is an official Apple over-the-air update for the iPad Air (China), released on 2018-09-18T17:20:05Z. The update package is 314.61 MB. This is a delta (partial) update that requires 12.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 4c770b47c8acca97e5df3e8e24f075d143abdf91.zip.