A3 877 then A3 674 at Athens
Budapest → Athens → Florence
Timetable, Athens time
19:20A3 877 from Budapest at the gate
16:35A3 674 to Florence leaves the gate
21 h 15 apart on the timetable, overnight
A3 674 leaves 21 h 15 after A3 877 arrives on the timetable: more than half a day, so not a connection we count.