iPadOS 11.3 (build 15E5216a) is an official Apple over-the-air update for the iPad Pro 12.9-inch (WiFi), released on 2018-03-16T17:05:11Z. The update package is 53.07 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a8f8b576f2da9c8dbfb72c9a9f7dd3a4b601cc71.zip.