PU 502 then W4 6312 at Madrid
Buenos Aires → Madrid → Milan
Timetable, Madrid time
15:45PU 502 from Buenos Aires at the gate
09:55W4 6312 to Milan leaves the gate
18 h 10 apart on the timetable, overnight
W4 6312 leaves 18 h 10 after PU 502 arrives on the timetable: more than half a day, so not a connection we count.