F9 1323 then B6 394 at Denver
Dallas-Fort Worth → Denver → Boston
Timetable, Denver time
12:08F9 1323 from Dallas-Fort Worth at the gate
12:05B6 394 to Boston leaves the gate
23 h 57 apart on the timetable, overnight
B6 394 leaves 23 h 57 after F9 1323 arrives on the timetable: more than half a day, so not a connection we count.