UA 4909 then AA 1869 at Houston
Huntsville → Houston → Miami
Timetable, Houston time
13:23UA 4909 from Huntsville at the gate
13:20AA 1869 to Miami leaves the gate
23 h 57 apart on the timetable, overnight
AA 1869 leaves 23 h 57 after UA 4909 arrives on the timetable: more than half a day, so not a connection we count.