provision for revised st returns

Time limit for filing revised return is 90 days from the date of submission of your original return.

If the value of taxable service changed the same has to be furnished in the revised return. Accordingly service tax has to be paid if the taxable value increased. Excess service tax paid can be adjusted to further period if the value of the taxable service decreased.

thanks for your reply...if value of taxable service is increased, the payment of service tax will be the actual amt or any interest will be paid for that delayed payment. kindly clarify... 

Yes. Interest must be paid for the delayed period along with the service tax payment.