DL 2599 then DL 1601 at Atlanta
Madison → Atlanta → Houston
Timetable, Atlanta time
22:59DL 2599 from Madison at the gate
22:41DL 1601 to Houston leaves the gate
23 h 42 apart on the timetable, overnight
DL 1601 leaves 23 h 42 after DL 2599 arrives on the timetable: more than half a day, so not a connection we count.