Where in the proceedings for assessment/re-assessment of any dealer for any period an order is passed ex parte the dealer may.

(a) if he had previous intimation of the date of hearing, within thirty days of the date of hearing; and

(b) if the dealer had no previous intimation of the date of hearing, within thirty days from the date of service of such order, apply to the Commissioner to set aside the order and reopen the case and if the Commissioner is satisfied that the applicant did not receive notice or was prevented by sufficient cause from appearing on the date fixed, he may set aside the order and reopen the case for hearing.

Provided that.

(i) no application for setting aside an ex parte assessment order shall be entertained unless it is accompanied by satisfactory proof of payment of the amount of tax admitted by the dealer.

(ii) such an application shall be entertained only once in the course of such proceeding.