ಮೈಸೂರು - ವಾರಣಾಸಿ ಎಕ್ಸ್‌ಪ್ರೆಸ್: ಕಾವೇರಿ ಮತ್ತು ಗಂಗಾ ನದಿಗಳ ಸಂಪರ್ಕ ಸೇತುವೆ - Vishwanath Joshi

YES..
you can change the boarding point at reservation counter.
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The request for change of Boarding Point should be submitted at least 24 hours before the scheduled departure of the Train from the station.
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Fill up a reservation form and enter your details and PNR no. with the new boarding station clearly mentioned
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Approach supervisor at the nearest Railway Reservation Office with with your ticket and the actual id [in original] mentioned therein.
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This facility will be given once only.