dil e nadaan

Does anyone know whether UMass usually sees movement on their waitlist? If yes, how many ppl do they accept from the waitlist each year? When do they extend offers of acceptance to those from the waitlist they wish to accept? And if they don't usually see movement on the waitlist, when do they send out rejection emails to the waitlisted folks? On 16 April? I understand no one will prolly know for sure but please share any reliable piece of info that you may have in this regard! Thank you!!