iPadOS 9.9.13.3.1 (build 17D50) is an official Apple over-the-air update for the iPad Pro 3 (12.9-inch, WiFi, 1TB Model), released on 2020-01-28T18:27:43Z. The update package is 3.11 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f7cdd8152678da7f469e3a7bdf435677881b0534.zip.