I had a chat with Sr. DOM Izzatnagar and he said the following..
1) No plans as such to divert the train via PBE-SBZ-SPN
2) Bareilly Jn NR along with Izzatnagar NER are high revenue generating stations hence diversion is not feasible
3) Will require reversal at PBE if terminating at TPU, looking in the train now has end to end electric loco traction...
more... and diversion will result in one reversal plus additional Diesel loco traction for 70 percent of journey which is undesirable.