BA 931 then IB 716 at Heathrow
Düsseldorf → London → Madrid
Timetable, London time
11:35BA 931 from Düsseldorf at the gate
11:25IB 716 to Madrid leaves the gate
23 h 50 apart on the timetable, overnight
IB 716 leaves 23 h 50 after BA 931 arrives on the timetable: more than half a day, so not a connection we count.