iPadOS 10.3.1 (build 14E304) is an official Apple over-the-air update for the iPad Air 2 (WiFi), released on 2017-04-03T17:00:11Z. The update package is 733.75 MB. This is a delta (partial) update that requires 10.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 674a233fd0721ada25f02693df9729d61b00fd8b.zip.