Você deve agende uma entrevista . Do site do CBP (erros tipográficos deles):
You must schedule an appointment within 30-days of receiving you conditional approval, but the actual interview date may be outside that window. Not scheduling the interview will result in cancelation of the application and no refunds will be granted. Also note that canceling an appointment that has reached the 30-day period from the date of conditional approval can cause your application to be cancelled. You may reschedule as often as needed outside of the 30 day window.