Please may i know advantage and disadvantages of drop box.
FYI I recently noticed below.
If you enter the United States under the Visa Waiver Program, you are not permitted to extend your stay in the United States beyond the initial admission period. You must depart the United States on or before the date on your admission stamp when you entered the United States. See Extend Your Stay on the U.S. Citizenship and Immigration Services (USCIS) website.