Well, now that I have read through it carefully, I think all of the above is incorrect. The Pre-Opening program is actually something no one is actually doing and it is questionable whether anyone would want to do it.
Let's start with how things would work if no Pre-Opening program exists. Does that mean DVC could not do what it is doing now, taking reservations for BLT (or AKV) for times after it opens? No. It could do exactly what it is doing now. The condition is that none of those reservations will mean squat if the darn thing doesn't actually get an occupancy permit and open by the date you are supposed to be there. And if it doesn't open, you lose your reservation but they will have to give you your points back (and you may be stuck with not being able to bank them or not being able to make another reservation for the same period elsewhere). Likewise, if they happen to "overbook," meaning they allow DVC members to reserve more time than DVC Members may be entitled to by the time of any given reservations, they could also cancel your reservation and give you your points back. That one is unlikely to occur because DVD can always allow use of more reservation time for DVC Members as long as rooms are open regardless of whether enough has been declared into the system, but it has the option to just cancel the reservation and give points back.
So what is this Pre-Opening Program? Exactly what it says it is and you need to actually request to do it. You can call to reserve at BLT (or other unopened resort). They can confirm that reservation (conditioned on the resort opening) but you in fact have not yet used your points for it yet. You are then required on the same call to make another reservation at another DVC resort (one that is actually open) using the same amount of points needed for the BLT reservation (it can be, but does not have to be, for the same time period as your BLT reservation). You are then deemed to assign that particular reservation to DVD in return for your BLT reservation, and DVD can go about renting the reservation you made at the other resort to others. Effect: if you then do not get your BLT reservation because the thing does not open, you don't get your points back. All DVD needs to do is give you a "replacement benefit of the type, quality, value and term reasonably similar to the Pre-opening Program [your BLT reservation]. Reservations at a DVC Resort [meaning any DVC resort] shall be deemed conclusively to be reasonably similar to the unavailable Pre-Opening Resort." In other words, DVD can give you a reservation for the same time period, same number of days, and for the same size room (studio, 1BR, 2BR) at any other DVC resort (most likely SSR) and you have to take it even if its point cost is less than what you used to reserve BLT and DVD doesn't have to give back any difference in points. It is hard to justify doing it except to give some confidence they will give you a reservation elsewhere for the same period or they will otherwise justly compensate you -- such as giving your points back and allowing you to bank them even if beyond a banking date -- because you gave them something of value, your other reservation, and did not get what you bargained for in return.
My best guess is no one has ever actually used the pre-opening program. My second guess is most at MS wouldn't even understand what it is if you called and asked to do it.