iPadOS 12.4 (build 16G5069a) is an official Apple over-the-air update for the iPad Air (Cellular), released on 2019-07-09T17:15:40Z. The update package is 255 MB. This is a delta (partial) update that requires 12.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c4c0104cbd4cd99aa7ca3734966de995a3569161.zip.