UA 331 then UA 1635 at Dulles
Houston → Washington → Atlanta (ATL)
Timetable, Washington time
20:33UA 331 from Houston at the gate
00:00UA 1635 to Atlanta (ATL) leaves the gate
3 h 27 apart on the timetable, overnight
The last days
UA 331 and UA 1635 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.