I don't know too much about ED other than as previously mentioned it's usually for people who absolutely cannot attend school anywhere else. If this is the case for you, since you are still in the running, I would try to impress upon the school the reasons why you did ED. There was some poster last year who talked about how, after getting waitlisted during his application year, he sat down and wrote a sincere letter of intent at his top choice. I'd say now is probably the time for a sincere, well-written letter of intent that highlights the reasons the program is best for you as well as throwing in some things about you that make you an asset to the program as well.