F9 3600 then B6 1396 at Atlanta
Denver → Atlanta → Boston
Timetable, Atlanta time
15:48F9 3600 from Denver at the gate
15:38B6 1396 to Boston leaves the gate
23 h 50 apart on the timetable, overnight
B6 1396 leaves 23 h 50 after F9 3600 arrives on the timetable: more than half a day, so not a connection we count.