I applied very early. TBH, the administrative staffs replying to our inquiries are very unprofessional. Sometimes I felt they had minimum ideas of what's going on. Every time I asked a simple question it took them one or two whole weeks to reply... And they sound like they are tired of their jobs..
However, I believe u still have a high chance to get in cuz it seems like they r rolling offers, and it seems like only 5 to 6 ppl got the offer since the course planning website indicates there are only 5 or 6 students enrolled in the biostats course. Good luck!