It is a pretty-much-always sort of thing if you already applied or filled out a form saying that you planned to. If you haven't had past interactions with this particular school, it is less common but not unheard of. My friend, who is an SM, and I were both contacted by various schools. Most colleges and universities recruit in various ways and I don't think that BFA programs are exempt from this. Can you give us a little more background information about your past interactions, or lack thereof, with the school?