iPadOS 11.3 (build 15E216) is an official Apple over-the-air update for the iPad mini 3 (Cellular), released on 2018-03-29T17:07:28Z. The update package is 607.94 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: 3be72a673cdca3137d9a1376db706ca4b949640f.zip.