iPadOS 12.4 (build 16G5046d) is an official Apple over-the-air update for the iPad mini 3 (WiFi), released on 2019-06-11T17:07:00Z. The update package is 224.1 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: abb13af7dbf11dac1bb2c0c37d0e85de7b9f01bf.zip.