BA 965 then BA 762 at Heathrow
Hamburg → London → Basel
Timetable, London time
21:30BA 965 from Hamburg at the gate
16:40BA 762 to Basel leaves the gate
19 h 10 apart on the timetable, overnight
BA 762 leaves 19 h 10 after BA 965 arrives on the timetable: more than half a day, so not a connection we count.