रेलफैनों की तो बात ही कुछ और है

I am planning to travel to Bikaner from Pune by 19th or 20th April. As there are no confirmed tickets available to Bikaner from Pune, both via Mumbai and via Jaipur / Jodhpur. Now my question is:
Is it possible to take an UNRESERVED ticket from PUNE to BIKANER via Manmad, Bhopal, KOTA, JAIPUR across the counter and then go to the reservation office and book reserved Berths for different laps of journey, as done when booking through a Circular Jouney Tkt?
Please advice.

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