You can certainly get the UPH, but you cannot buy it in advance. That means you end up paying the "gate" prices and miss out on the advance purchase discount.
You MAY be offered the DVC Member discount, which is 10% off the regular price. However, more and more frequently vendors are asking to see the actual DVC membership card before granting discounts. So, I wouldn't count on getting any discounts, but you may be pleasantly surprised.