¹[30A. Notwithstanding anything contained in any other law for the time being in force or any decision of any Court, for the purposes of section 30, the value and the rate of duty applicable to any goods shall respectively include the value as determined under section 25 and any amount of duty imposed under section 18, 18A or 18B and the amount of duty that may have become payable in consequence of the withdrawal of the whole or any part of the exemption or concession from duty whether before or after the conclusion of a contract or agreement for the sale of such goods or opening of a letter of credit in respect thereof.]