What I have "heard" (read) is that they are charging those who made the online reservation, pre-cruise the full price (that is to say...the price that they paid online, not full onboard price)...IOW, they are not allowing them to use the pre-made reservation as one of their package meals. I really think it's dependent upon the ship and who you get to help you with the "conversion". I think you will be in a better position if you have the UDP than if you have only a 3-night package. Hopefully it's much ado about nothing and you will be fine.