ECO - Early Connection Opportunity

Anyone else have their acceptance contingent upon successful completion of the ECO? Does anyone know why some are required to do ECO and others are not? The 4 week program ends 8/5/16 and I believe fall semester classes begin 8/31/16 so what happens in that gap? Do we remain on campus for the beginning of the term, or go home and come back? Coming from out of state, this is helpful information to know. Thanks!