There is almost always some degree of public soft opening before AP previews. For MSpace for example, public previews took place months before AP Previews. The AP previews are relatively "hard dates", in that they are planned and advertised, so the attraction has to be ready at that time. The public soft openings before the AP dates can occur at anytime, as they are unannounced. I would say the order will more liekly be:
CM Previews
Public Soft opens
AP Events
Official Opening
CM Previews
Public Soft opens
AP Events
Official Opening