iPadOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2019-01-22T18:04:05Z. The update package is 1.2 GB. This is a delta (partial) update that requires 11.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 408fcbcf51dd9209041c033aac7b710167ec70fd.zip.