plzz help regarding DD problem

CA Prem. (CA ) (345 Points)

03 March 2011  

hey guys me cleared my IPCC exam held in month of Nov....I was suppose to register for final on 28th feb 2011 ....however due to some problem now iam going to register on 1st april 2011....my problem is that i had already made a DD dated 28th feb 2011....so can i use the same DD for 1st april registraion........for how many months a DD valid??? ...plzz help