W6 4401 then FR 5997 at Madrid
Sofia → Madrid → London Stansted
Timetable, Madrid time
19:50W6 4401 from Sofia at the gate
17:40FR 5997 to London Stansted leaves the gate
21 h 50 apart on the timetable, overnight
FR 5997 leaves 21 h 50 after W6 4401 arrives on the timetable: more than half a day, so not a connection we count.