SG 612 then QP 1256 at Mumbai
New Delhi → Mumbai → Kolkata
Timetable, Mumbai time
22:15SG 612 from New Delhi at the gate
22:05QP 1256 to Kolkata leaves the gate
23 h 50 apart on the timetable, overnight
QP 1256 leaves 23 h 50 after SG 612 arrives on the timetable: more than half a day, so not a connection we count.