TP 1359 then FR 1791 at Lisbon
London Heathrow → Lisbon → Luxembourg
Timetable, Lisbon time
16:30TP 1359 from London Heathrow at the gate
14:25FR 1791 to Luxembourg leaves the gate
21 h 55 apart on the timetable, overnight
FR 1791 leaves 21 h 55 after TP 1359 arrives on the timetable: more than half a day, so not a connection we count.