iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone SE, released on 2019-01-22T18:11:52Z. The update package is 1.7 GB. This is a delta (partial) update that requires 10.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ec418faf911d410f6bd0bdbc43eadea3925642ec.zip.