AA 712 then AA 5893 at Charlotte
St Louis → Charlotte → Florence
Timetable, Charlotte time
10:13AA 712 from St Louis at the gate
22:50AA 5893 to Florence leaves the gate
12 h 37 apart on the timetable
AA 5893 leaves 12 h 37 after AA 712 arrives on the timetable: more than half a day, so not a connection we count.