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 564.78 MB. This is a delta (partial) update that requires 10.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3e75320475f2ba4b1931a6a21b9d98e61d40483c.zip.