iPadOS 11.3 (build 15E216) is an official Apple over-the-air update for the iPad 5 (Cellular), released on 2018-03-29T17:10:25Z. The update package is 584.68 MB. This is a delta (partial) update that requires 11.2.6 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 602093105deb035d72b5681768c234b3189cb8dd.zip.