iPadOS 12.4 (build 16G5056d) is an official Apple over-the-air update for the iPad Air (China), released on 2019-06-24T17:16:48Z. The update package is 259.04 MB. This is a delta (partial) update that requires 12.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2406ae4636701cf6c04f009bb2767e6252d66089.zip.