Sir approval of TDR also depends on zone. As i seen WCR clears TDR too fast whereas CR takes enough time to approve a TDR and if they approve they didn't provide full amount refund. There are 2 cases of mine in which The train is late more than three hours and i have to get full refund but CR given only 50% amount back. :(
PS :- I am not referring to a single zone it is based upon my experience.