iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad mini 2 (WiFi), released on 2018-04-24T17:05:53Z. The update package is 672.66 MB. This is a delta (partial) update that requires 11.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9c67adcb03a7a39eadf4f619d3896a2583da57dc.zip.