iPadOS 12.1.3 (build 16D5037a) is an official Apple over-the-air update for the iPad Air (WiFi), released on 2019-01-07T18:06:16Z. The update package is 65.21 MB. This is a delta (partial) update that requires 12.1.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: de14c64c7c3047e2e6b1c86b884f67214d462f21.zip.