RailFanning is a gift you give yourself. - Varun

Yes the same thing I informed in my post # 36468-5.
... in case of counter ticket..... original ticket at the time of boarding change .....
.....in case of e-ticket ... ...... print out of e-ticket .....
@ Explanatory posting for for e-tickets ........
Print...
more...

out of e-ticket means either print out or even zerox of that print out copy as you can have many print outs for the same e-ticket .... so what if it's zerox copy of the print out. Is zerox copy of e-ticket not acceptable alongwith one of the id proofs ? It's acceptable and hence it's also acceptable for boarding change process.
Only requirement is presentation of e-ticket.... on which endoresement will be made and then that copy or print out will become final ticket document to be shown to the TTE while travelling. Based on the PNR No.. the PRS booking will make necessary boarding station changes in the Reservation system which will take care at the time of chart preparation. The TTE will have the copy of the chart wherein all these details are available.