iPadOS 11.4 (build 15F5079a) is an official Apple over-the-air update for the iPad mini 2 (China), released on 2018-05-17T17:01:55Z. The update package is 38.87 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: d8676b4501bf482ef430af5c1a63be3dbb22f56b.zip.