Yes i recieved that email too. It is really weird, because I am sure that people are telling them that they are interested in attending BUSDM, but they continue to send out emails asking everyone if they are still interested in the program. I know a few people that have gotten off the waitlist, so my guess is to sit tight till the 31st.
I was on the waiting list and got accepted on the 3rd(july). I requested for deferral so if they let me defer my acceptance, there will be another spot opening. good luck