It is quite possible Suman, because of loco reversal for this train at Durgapur. The train takes the Siuri-Andal-Durgapur route and then the Durgapur-Andal-Raniganj-Asansol route after the loco reversal at Durgapur. The same thing happens to the Dibrugarh - Chennai and Guwahati - Chennai Expresses and maybe a few other trains, which I dont remember.