Champaran HumSafar Express : इन अजनबी सी राहों में, जो तू मेरा हमसफ़र हो जाये, बीत जाए पल भर में ये वक़्त, और हसीन सफ़र हो जाये. - Piyush Singh

CHANGE OF BOARDING POINT :
If a passenger desires to occupy reserved accommodation from any station enroute, he would be permitted to entrain at any intermediate station he chooses irrespective of the distance from the starting station subject to the following conditions :
A specific request must be made in writing at the station from where the ticket is purchased and reservation made atleast 24 hours before the scheduled departure of the train from the starting station.
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Railway Administration reserves the right to use such accommodation from the originating station up to the station at which the passenger is due to entrain.
No refund will be permissible for the portion of journey not performed by the passenger.
Source : Indianrail.gov.in