6E 2125 then SG 553 at Mumbai
Chennai → Mumbai → Gorakhpur
Timetable, Mumbai time
18:056E 2125 from Chennai at the gate
17:15SG 553 to Gorakhpur leaves the gate
23 h 10 apart on the timetable, overnight
SG 553 leaves 23 h 10 after 6E 2125 arrives on the timetable: more than half a day, so not a connection we count.