I think it's very clear and still the same like any other MMO.
When you buy the game, you get 30 days of free game time.
However, in order to play the game you must have an ACTIVE subscription.
Whether this is by PayPal, Visa or Game Time Card is up to you.
If you want to pay recurring fees through Paypal or Visa, you will not get billed untill your initial free 30 day period is over. After this first period you will get bill via your selected payment method.
If you don't want to use a recurring billing cycle, you can choose to pay with game time cards. In order to play, however, you must activate a valid game time card.
YOU CANNOT PLAY UNTILL YOU REGISTERED YOUR VISA CARD, PAYPAL ACCOUNT, OR GAME TIME CARD, EVEN IF YOU HAVE 30 FREE DAYS WORTH OF GAMETIME.
Once again, if you sign up for a recurring subscription, you do not get billed untill your free 30 days are over. If you use a game time card, you will have: 30 free days + amount of days added through game time. You cannot play untill you selected a method.
Hope this helps.
Anve