iOS version 9.3.2 includes bug when trying to change management state for already installed (by the user) application to managed installation. It always failed with error "The iTunes Store ID of the application could not be validated" if application wasn't already found in the user's purchase history.
When installing applications regularly without volume purchasing program (VPP) to iOS 9.3.2 device, we don't set the ChangeManagementState parameter. If the application is not installed on the device, there's no disadvantages. If the application is already installed by the user, then the application installation fails. This is still a smaller problem than the original problem, when the installation failed on iOS version 9.3.2 most of the times.
When installing applications using VPP licensing, we include the ChangeManagementState parameter, because it works with already assigned VPP licenses.
We hope, that Apple has fixed this in iOS version 9.3.3. [Update 2016/08/01: NO THEY HAVEN'T FIXED IT! - but this workaround works now also on 9.3.3]
Update 2016-09-27 - Looks like this has been fixed in iOS 10.
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