FR 270 then FR 8231 at Barcelona
Milan → Barcelona → London Stansted
Timetable, Barcelona time
17:10FR 270 from Milan at the gate
08:15FR 8231 to London Stansted leaves the gate
15 h 05 apart on the timetable, overnight
FR 8231 leaves 15 h 05 after FR 270 arrives on the timetable: more than half a day, so not a connection we count.