Sunday morning we drove from our house, near I-40 and Choctaw Road, to the 501 Cafe in Edmond (501 S. Blvd). It took about 40 minutes, north on I-35, then city streets to the restaurant. Monday night we're going to their monthly special dinner, with a reservation at 6:30. How much extra time should we allow because we'll be doing it during rush hour? Thanks.