I dont think your logic is correct.Even 15767 NJP-APDJ I/C Exp runs 167 km in 4 Hrs & frequently it gets delayed by upto 2-4 Hrs.Whatever time it reaches APDJ,even if at midnight its always crowded....Infact 11 GS Coaches are not enough...Lot of DP's there travelling b/w Siliguri & different parts of Dooars.