If train missed or cancelled or diverted, TDR for E-Ticket as well as PNR Ticket can be filed.
For Cancelled/diverted trains, u get full return (minus clerical charges) & for missed trains, u get 50% back.
For PRS Ticket, refund is real-time, while for E-Ticket (TDR filed online thru the account from which booking was made), its 3 months time-boundation.
PS: E-Ticket TDR,...
more... has been cleared in 4-5 days, 3 months, years & sometimes never!!
No TDR for Tatkal Tickets