This used to be the case 3-4 years ago when Udyan was coming from Mumbai with 18 coaches and 4 coaches were added at Solapur. Then, they changed to 22 coaches right from Mumbai. So I don't think this is a true statement as of now. I did see some newspaper reports of a PC planned for this train, which would be locked up when it runs as Siddeshwar. However, nothing seems to have come out of it. I personally dislike this train being paired with Siddeshwar. The train has become filthier and always runs behind schedule. This train deserves a little speeding up and a rake of its own.