Convert a Public App to a Private App

Hello, in App Store Connect it appears that it is possible to convert a public app that is currently in the App Store to a private app that is only available to authorized users through Apple Business Manager and Apple School Manager.

My quests are:

  1. Is this truly possible?
  2. After the app is converted, will existing users be able to continue to receive updates or reinstall the app?

Hopefully, someone has done this and knows the answers. Thanks!