AI 2580 then SG 622 at Mumbai
Udaipur → Mumbai → Varanasi
Timetable, Mumbai time
14:30AI 2580 from Udaipur at the gate
10:40SG 622 to Varanasi leaves the gate
20 h 10 apart on the timetable, overnight
SG 622 leaves 20 h 10 after AI 2580 arrives on the timetable: more than half a day, so not a connection we count.