AA 4040 then AA 6355 at Phoenix
Denver → Phoenix → St George
Timetable, Phoenix time
07:07AA 4040 from Denver at the gate
20:00AA 6355 to St George leaves the gate
12 h 53 apart on the timetable
AA 6355 leaves 12 h 53 after AA 4040 arrives on the timetable: more than half a day, so not a connection we count.