What happens if... (expansion question)

[peaches]

You can play XIV on any computer with the game downloaded, provided it has the same content downloaded.

If you have Heavensward, and you use a friend's computer who doesn't own Heavensward, what happens? If you can access all the content like normal, that's cool. And it should be like that on the PS4 as well, but it won't be. With other MMOs I've played either the game itself is a free download, but you can only log on with an active account with a game licence. You could torrent the game for all it matters, as long as you have an active account. I'd prefer if XIV was the same way, cross system.