Our son held on to his EA school until he was safely through basic training (mid August) prior to entering USMA as injuries can cause turnbacks. The service academies recommend holding on to Plan B as insurance against this possibility. The EA college was fine with this. No one is harmed as all colleges over-admit expecting declines and no-shows, waitlists are deep, and none of the colleges coveted here ever find themselves underenrolled. Do what makes sense for your family and don’t give it another thought.
ETA: We did lose the deposit, but small price to pay.