AA 6510 then AA 1594 at Phoenix
Burbank → Phoenix → Austin
Timetable, Phoenix time
19:26AA 6510 from Burbank at the gate
13:58AA 1594 to Austin leaves the gate
18 h 32 apart on the timetable, overnight
AA 1594 leaves 18 h 32 after AA 6510 arrives on the timetable: more than half a day, so not a connection we count.