SEE has a DEMU maintenance shed. So every morning 75213 starts from SEE for PPTA. This rake departs as 75216 as PPTA-BJU DEMU. Again it comes back to PPTA as 75215 BJU-PPTA DEMU and finally leaves PPTA for SEE as 75214 DEMU at the day's end for maintenance at DEMU maintenance shed. So extension is not possible.