Refund of verification fees by icai

hi friends,

for May 2012 IPCC examination i have applied for Verification of Answer books and Certified copies of answer books and

i got a letter from institute stating  change in marks has been found but there is no change in results and they have mentioned that your refund will be informed shortly, how many day it will take them to send a refund and the mode of refund  i wanted to know last time also i got a same type of letter but i have not got the refund still.

please anyone letme know about this .