Buy an open unreserved ticket from Kalyan to BSR and board the train. The berths for the six of you are likely to be vacant. Occupy the same. When TTE comes explain and pay the difference in fare. The TTE will certainly accept the same and there won't be any problem.

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Thanks Sir. But do you think this is right as per railway rules?? I mean 99% of the times the TTE wouldnt say anything but just in case..

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It is the right procedure as per railway rules. The TTE is bound to allot the vacant berth up to the station it is vacant. Better and fool proof would be that you can book berth by the same train and class between the desired stations. It is more likely you are allotted one of the six berths. Even if it is not you can occupy your original berth as it would certainly be vacant.

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