Yes Boarding can easily be changed for the both the cases: Counter Ticket or Online while booking Ticket.
Please have a look on my blog /blog/post/1337761 Screenshot is also attached for help.
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Boarding Point can be changed easily for any trains.
It...
more... is just required:
1. Photocopy/ Xerox of the e-ticket. Original copy for counter booked ticket.
2. Photocopy/ Xerox of ID proof of travellers.
NOTE: Your berth status won't change from the source booking station. The berth quota won't be given for the boarding station.
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For on-line tickets also, Boarding Point can be changed easily for any trains:
1. On the passenger detail page, you will find "Boarding Point".
2. Click on it to change your desired boarding point.
PFA screenshot for more help.
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I hope this helps.
Thanks