iPadOS 9.3.1 (build 13E238) is an official Apple over-the-air update for the iPad Pro 12.9-inch (Cellular), released on 2016-03-31T16:54:27Z. The update package is 293.7 MB. This is a delta (partial) update that requires 9.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 0e3fd81b86b7eeaf7df082d5a1053a6ff228b476.zip.