iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad Pro 2 (12.9-inch, WiFi), released on 2018-04-24T17:08:59Z. The update package is 33.18 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1c83700479f5d21c2b760c4a9f2206961cff4bbd.zip.