EC 4389 then IB 721 at Madrid
Lyon → Madrid → London Heathrow
Timetable, Madrid time
17:00EC 4389 from Lyon at the gate
15:50IB 721 to London Heathrow leaves the gatealso LA 1701, VY 5176, DT 6160, QR 6906, BA 7068, AA 8652
22 h 50 apart on the timetable, overnight
IB 721 leaves 22 h 50 after EC 4389 arrives on the timetable: more than half a day, so not a connection we count.