iOS 13.4 (build 17E5223h) is an official Apple over-the-air update for the iPhone 11 Pro Max, released on 2020-02-05T18:17:33Z. The update package is 830.02 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: c5d30a8fcec5da765f4420ce9d7552e93721ee0a.zip.