BA 713 then BA 814 at Heathrow
Zurich → London → Copenhagen
Timetable, London time
14:30BA 713 from Zurich at the gate
14:15BA 814 to Copenhagen leaves the gate
23 h 45 apart on the timetable, overnight
BA 814 leaves 23 h 45 after BA 713 arrives on the timetable: more than half a day, so not a connection we count.