iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad 5 (Cellular), released on 2018-04-24T17:08:11Z. The update package is 624.19 MB. This is a delta (partial) update that requires 11.2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d93221397d3a1e115d1d185fa7d5dcf1386e2fb2.zip.