iPadOS 12.3 (build 16F5148a) is an official Apple over-the-air update for the iPad Pro 3 (12.9-inch, Cellular, 1TB Model), released on 2019-04-29T17:35:59Z. The update package is 473.51 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: 01ca1ba5cf5f9835319100ec2941911201f8a006.zip.