Ha ha they never told Premium trains will be of faster/high speed services :P
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Refer this.The Unique features of ‘Premium’ train service are:
1) ‘Premium special train´ is a fully reserved service aimed to meet the heavy demand for Rail travel during busy season o­n popular routes. It is primarily targeted at that segment of passengers, who are willing to pay premium fare...
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for confirmed berths at the time of booking itself availing enhanced standards of service.
2) The fare structure for this Premium Special Train is variable and follows a dynamic pricing model. The fare will also include catering charges.
3) The booking of tickets can be done o­nly through IRCTC’s portal o­n internet. Tickets will not be issued manually at reservation counters. However, vacant berths available after charting will be offered at current day booking counters at the train originating stations.
4) Only confirmed tickets will be issued for Premium Trains. Waitlisted tickets will not be issued. There will be no refund except when the train is fully cancelled o­n railway account due to unforeseen circumstances. Adult fare shall be charged for all passengers irrespective of their age. No concession shall be applicable to this train. Ticket modifications/issue of duplicate ticket etc., are not permitted.