Thank you everyone. I think we need to either fly in the morning with Delta or consider other airlines to fly in the evening. One option from Capital One Travel is BNA-ATL-ICN-OKA, departure from BNA at 5:40pm and arrived Okinawa at 10:25am, the last leg will be operated by Korean Air. There is about 2.5 hrs layover at ICN, is it enough time to catch the next flight?