iOS 12.1.3 (build 16D39) is an official Apple over-the-air update for the iPhone SE, released on 2019-01-22T18:12:20Z. The update package is 1.29 GB. This is a delta (partial) update that requires 11.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 4f8d37790adc4da4572c3da6682601160a773fd7.zip.