iPadOS 11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad mini 4 (Cellular), released on 2018-04-24T17:07:22Z. The update package is 735.44 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2f15f9fb47dd397991092f88321870cca6d68ff6.zip.