The proper officer shall issue show cause notice at least 3 months prior to the time limit of 3 years for issuance of order i.e.
Before completion of 3 years from the due date for furnishing of annual return for the financial year to which the tax not paid or short paid or input tax credit wrongly availed or utilized relates to, or
within 3 years from the date of erroneous refund, as the case may be.
9ICAI FAQ PUBLICATIONS 06-09-2017 Determination of tax not paid or short paid or erroneously refunded or input tax credit wrongly availed or utilized for any reason other than fraud or any willful misstatement or suppression of facts : FAQ NO. 2)