You make it sound like all rooms at POR with Murphy beds are Preferred. That is not the case. You can book a Standard room and still get a Murphy bed.
If all the rooms in Jamaica had them and no other Villages did then I could see them making Jamaica Preferred.
I am not being clear, I guess. What I mean is that if you want a guaranteed murphy bed, you have to pick preferred. You can still get a murphy bed if you pick standard, of course, but that is only a request. If you pick preferred, you are guaranteed. That is the difference, and I am wondering if this is how they will do it once you can book specific new rooms at CBR.
It doesn't matter as really - I will have this answered for me in a few months.