iPadOS 11.3 (build 15E5189f) is an official Apple over-the-air update for the iPad Air 2 (WiFi), released on 2018-02-20T18:06:16Z. The update package is 292.8 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 8f982e01282fe1064b60252bfc804ff0f62355fc.zip.