AA 3746 then AA 6238 at DFW
Billings → Dallas-Fort Worth → Amarillo
Timetable, Dallas-Fort Worth time
11:05AA 3746 from Billings at the gate
08:25AA 6238 to Amarillo leaves the gate
21 h 20 apart on the timetable, overnight
AA 6238 leaves 21 h 20 after AA 3746 arrives on the timetable: more than half a day, so not a connection we count.