iPadOS 12.1.1 (build 16C50) is an official Apple over-the-air update for the iPad Air 2 (WiFi), released on 2018-12-05T18:08:23Z. The update package is 1.19 GB. This is a delta (partial) update that requires 11.4.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 25fa5deb7262f09562bc4117227c89243cec86b9.zip.