iPadOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPad Pro 12.9-inch (WiFi), released on 2019-01-22T18:07:22Z. The update package is 1.25 GB. This is a delta (partial) update that requires 11.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9c52491872db4953cf99936e4495992291d60921.zip.