Early Action chances

Many T50 schools including all the Ivys highly recommend that both recruited athletes and legacy and faculty children apply either ED or REA to benefit from the preferential treatment afforded them by their "hooked" status.

While it's not mandatory to apply early, what is true is that the supply of seats available to "hooked" applicants are the first to be filled up so there is no upside to being "hooked" and applying RD unless you want to use the extra time to improve aspects of your academic or EC narrative to make you a more compelling applicant.

For example, Columbia has a fixed 650 ED seats to dole out each year. It's not 625 or 700 it's exactly 650 regardless of how many applicants apply during ED. So if you are a Columbia legacy, it's to your advantage to apply ED since nearly a 1/3 of those seats go to recruited athletes, another 10%+ to Questbridge, another 4% to Faculty kids, and 1-2% to VIPs or rich development candidates. So there are really only 325 seats and about 50 are going to legacy applicants (7%). Non-hooked applicants are left to compete for the 275 seats left which makes the ED admit rate about 4.7%, not 11.3%.

So if you really want to leverage legacy status, it always makes sense to apply early since the benefit of a 30X bump will offset any less-than-perfect grades, test scores, or course rigor. Otherwise, you are lumped into a bigger more diluted pool of applicants during RD and the AOs might not think you were that committed to attend.

Good luck.