Using TestFlight to distribute Enterprise in-house application

If you are a registered developer with an enterprise account and are making apps for in-house distribution, TestFlight works with those too. TestFlight fully supports enterprise apps and it works much like ad hoc apps for distribution. Just upload an application signed with an enterprise provisioning profile and distribute to your team and only approved members of your team will have access to the application for installation. There is no need to collect device UDIDs for enterprise.

This is response from TestFlight support, so NO, there is no need for collecting device UDIDs and it should work just like I wrote (just invite people to team via email / register link and approve them and they can download the enterprise app) :-)

Works the same.

If you are a registered developer with an enterprise account and are making apps for in-house distribution, TestFlight works with those too. TestFlight fully supports enterprise apps and it works much like ad hoc apps for distribution. Just upload an application signed with an enterprise provisioning profile and distribute to your team and only approved members of your team will have access to the application for installation.

http://help.testflightapp.com/customer/portal/articles/835394-what-about-enterprise-apps-

The answer is no, Enterprise accounts don't have access to testflight distribution. See https://help.apple.com/xcode/mac/current/#/devba5e7054d which states:

"Note: As a member of the Apple Developer Enterprise Program, you don’t have an App Store Connect account and consequently, the ability to distribute an app using TestFlight."