BA 483 then BA 838 at Heathrow
Barcelona → London → Dublin
Timetable, London time
19:25BA 483 from Barcelona at the gate
18:25BA 838 to Dublin leaves the gate
23 h apart on the timetable, overnight
BA 838 leaves 23 h after BA 483 arrives on the timetable: more than half a day, so not a connection we count.