DL 4731 then B6 1223 at JFK
Rochester → New York → Los Angeles
Timetable, New York time
17:50DL 4731 from Rochester at the gate
16:48B6 1223 to Los Angeles leaves the gate
22 h 58 apart on the timetable, overnight
B6 1223 leaves 22 h 58 after DL 4731 arrives on the timetable: more than half a day, so not a connection we count.