iPadOS 9.9.11.3.1 (build 15E302) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2018-04-24T17:05:09Z. The update package is 1.33 GB. This is a delta (partial) update that requires 9.3.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 273f8317052cf1877197d304da718519bc8a1f33.zip.