iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad Pro 12.9-inch (WiFi), released on 2018-04-24T17:08:43Z. The update package is 678.18 MB. This is a delta (partial) update that requires 11.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 95e4c1beaf35e6c63842b93e39b0d05c5a7039d0.zip.