Linda, as far as I know, last year's discount was available through all of January (check mousesavers for historical codes information), so I think you would be fine. However, availability might be limited. I don't how you have booked your room so far, but perhaps you could at least turn over the weekend booking to a specialized
Disney travel agent who will then monitor the codes for you and try to apply it when one comes out.
Dreams Unlimited is a sponsor of the disboards, other websites have other sponsors. Just calling Disney reservations without knowing the code is not going to help. I think they are not allowed to offer codes to someone who does not know them yet.