iPadOS 12.4 (build 16G5038d) is an official Apple over-the-air update for the iPad Pro 3 (12.9-inch, WiFi), released on 2019-05-28T17:07:31Z. The update package is 286.89 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: e5c5d232ecf847b66e18fa55938c7d04b3a9ac99.zip.