iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad 5 (Cellular), released on 2018-04-24T17:08:08Z. The update package is 745.87 MB. This is a delta (partial) update that requires 11.0.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ad800f384b779bc2bb8e5980525682a1721826d3.zip.