I just wanted inquire about this to make sure otherwise I'll keep having doubts. I understand that if you accept an offer which isn't your first preference in the main round you can withdraw your offer in the second round and accept another one above (if offered). My question is will I also be able to cancel the enrollment I made with the institution from my main round offer as well? or should I not enroll and wait until after the second round offers are out and then enroll?