That's what I am wondering. Who releases a game and demands pre-authorized payment without giving the 30-day free first, without having one of their main payment options in stores? They should have been released and on store shelves on March 1st in preparation for Launch.
By the way, the prepaid cards are 60-day only. No month to month option.
They are actually already available in some countries, just got one today myself. I suppose it's the retailers decision not to provide them, not really Zenimax' choice or fault.