EC 8064 then VY 7502 at Gatwick
Barcelona → London → Seville
Timetable, London time
15:00EC 8064 from Barcelona at the gate
09:35VY 7502 to Seville leaves the gate
18 h 35 apart on the timetable, overnight
VY 7502 leaves 18 h 35 after EC 8064 arrives on the timetable: more than half a day, so not a connection we count.