iPadOS 11.4 (build 15F5071a) is an official Apple over-the-air update for the iPad mini 4 (Cellular), released on 2018-05-07T17:11:09Z. The update package is 198.53 MB. This is a delta (partial) update that requires 11.4 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5e984916215f6f8d35934e0a5e050134d5e49191.zip.