iOS 11.3 (build 15E216) is an official Apple over-the-air update for the iPhone SE, released on 2018-03-29T17:13:06Z. The update package is 1.31 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: 3244f55fefbdd900a8adc9cb8b5295c5a902f3e6.zip.