WN 199 then DL 726 at Atlanta
Dallas → Atlanta → Boston
Timetable, Atlanta time
13:55WN 199 from Dallas at the gate
13:50DL 726 to Boston leaves the gate
23 h 55 apart on the timetable, overnight
DL 726 leaves 23 h 55 after WN 199 arrives on the timetable: more than half a day, so not a connection we count.