iPadOS 12.1 (build 16B92) is an official Apple over-the-air update for the iPad Air 2 (WiFi), released on 2018-10-30T17:05:55Z. The update package is 337.03 MB. This is a delta (partial) update that requires 12.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 37b7f08bce8b8106fab8ea2a5f95aa61151af64c.zip.