My nephews and nieces attended a private school that had this policy. You are unlikely to get better results in RD as @EmptyNestSoon2 said.
Your school counselors and administration are likely to take a dim view of your attempts to back out of your agreement. It can affect school admissions results for years to come. You and your parents probably signed something that said you would treat REA as binding. You are likely not the first family who has tried to back out. It’s a fight you’re unlikely to win.