iPadOS 12.1.1 (build 16C50) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2018-12-05T18:07:16Z. The update package is 1.2 GB. This is a delta (partial) update that requires 11.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 47f1d7c863cf8dae7a1818ff7a6b59e839bb665a.zip.