Explain about CCU in Unity3d Multiplayer?

Question

Game development

The Unity Personal edition lists 20 CCUs, i.e. y in my game, on the network, only 20 people can play at the same time, and the rest will not be able to connect? Or can 20 connect for free, while the rest pay 49 cents per gigabyte?
ps Live mode should be enabled after the final release of the game? (well, switching to Pro / Plus, because it is disabled in Personal)
pps https://poqxert.ru/blog/news/novaya-sistema-liczen... - "Unity Multiplayer - 20 CCU, but as far as this number is known for tests, the release pays for data transfer, and not for users."