iPadOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPad Air 2 (WiFi), released on 2017-12-13T18:08:09Z. The update package is 1.04 GB. This is a delta (partial) update that requires 10.3.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f920ae45732a3ab6e6e5a8c8d4c3b93d81dbfaa6.zip.