iPadOS 13.4 (build 17E5255a) is an official Apple over-the-air update for the iPad Pro 3 (12.9-inch, Cellular), released on 2020-03-10T17:21:18Z. The update package is 824.14 MB. This is a delta (partial) update that requires 13.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1e175073e1b6aeb266c12dca2b342b146d8855b3.zip.