IB 346 then IB 1411 at Madrid
Boston → Madrid → Prague
Timetable, Madrid time
08:05IB 346 from Boston at the gate
17:00IB 1411 to Prague leaves the gate
8 h 55 apart on the timetable
The last days
IB 346 and IB 1411 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.