我们学校网站是这么写的:You may enter the U.S. in F-1 or J-1 status up to 30-days before the program start date on your I-20 or DS-2019 (9/1/2020). You should arrive no later than the initial session start date or start of classes (09/29/2020). As these dates are determined based on the academic calendar, mid-quarter/late start dates cannot be accommodated. Any attempts to enter the U.S. after the initial session start date listed on your I-20 are not advised and are subject to CBP's (Customs and Border Protection) discretion.