iPadOS 12.1.3 (build 16D5032a) is an official Apple over-the-air update for the iPad 5 (Cellular), released on 2018-12-19T18:06:41Z. The update package is 235.59 MB. This is a delta (partial) update that requires 12.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f36f441c3288d4f13914aba395f8ae61759bf3dd.zip.