FR 3073 then FR 8231 at Barcelona
Prague → Barcelona → London Stansted
Timetable, Barcelona time
11:15FR 3073 from Prague at the gate
08:15FR 8231 to London Stansted leaves the gate
21 h apart on the timetable, overnight
FR 8231 leaves 21 h after FR 3073 arrives on the timetable: more than half a day, so not a connection we count.