I am traveling right now. I am going to get back April 9th. I have gotten into a few schools, which are pressuring me to decide about revisit weekends. I am still waiting to hear from a bunch of schools. I know that a lot of the revisit dates are going to overlap and I don't have a solid ranking of programs in my mind, but have sort of have a tier system (ie. school x comes before y or z). I think that I will want to visit say 2 or 3 schools before I make a final decision. If all of those revisits can't be scheduled before April 15th, and I don't think that they will, will schools allow me to delay my decision?