AA 3521 then AA 3939 at Charlotte
Valparaiso → Charlotte → Key West
Timetable, Charlotte time
15:37AA 3521 from Valparaiso at the gate
15:35AA 3939 to Key West leaves the gate
23 h 58 apart on the timetable, overnight
AA 3939 leaves 23 h 58 after AA 3521 arrives on the timetable: more than half a day, so not a connection we count.