iPadOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPad mini 3 (China), released on 2019-01-22T18:05:16Z. The update package is 388.44 MB. This is a delta (partial) update that requires 12.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: defcffc8b08fe4a14d38524598ad3f0e91904474.zip.