Current Booking (Booking against vacant accommodation after charting) Guide lines?

Booking is allowed for all types of users (Normal & Agent).
Only e-Ticket booking is allowed.
Only Confirmed tickets shall be booked during current booking.
Only senior citizen and disabled concession shall be allowed.
Current booking is allowed after charting within the existing booking time limit specified by Railways.
Boarding point change is not allowed for current booking PNR.
Name/age/gender change is not allowed for current booking PNR.
Booking in premium & Suvidha train will be allowed with the last booking fare.