Thanks a lot for the info PMM
Is there any official link which states that FBI is valid only for three months.
From the application instructions
:Note: If you are including your police certificates with your application to the CIO, please ensure that your certificates were not issued more than three months earlier.
Police certificates are generally valid for 12 months from the date they are issued. However, if a final decision is not made on your application before the expiry of your police certificate, the visa office may request that you provide a new one."