iPadOS 11.4 (build 15F5049c) is an official Apple over-the-air update for the iPad Air (China), released on 2018-04-16T17:07:26Z. The update package is 182.86 MB. This is a delta (partial) update that requires 11.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 6d94ea72696bfcc323f9da1d3cbfbbd26b7cf029.zip.