iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone SE, released on 2019-01-22T18:11:48Z. The update package is 1.7 GB. This is a delta (partial) update that requires 10.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f68ed8bbfd62f8dc2823fdad66dc2d9443b8001e.zip.