iPadOS 12.4 (build 16G5046d) is an official Apple over-the-air update for the iPad mini 3 (China), released on 2019-06-11T17:07:02Z. The update package is 224.05 MB. This is a delta (partial) update that requires 12.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c3d00209d9b202dbd1086b690d6310b9ab24c8d7.zip.