iPadOS 12.3 (build 16F5129d) is an official Apple over-the-air update for the iPad Pro 3 (12.9-inch, Cellular), released on 2019-04-08T17:04:44Z. The update package is 387.11 MB. This is a delta (partial) update that requires 12.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f8c8f1b208e169d36fae96be6bd007635f7bf57f.zip.