Advance ruling void for fraud or misrepresentation - authority may declare ruling void ab initio after hearing. Where the Authority or Appellate Authority finds an advance ruling was obtained by fraud, suppression of material facts, or misrepresentation, it may declare the ruling void ab initio, making the Act and rules apply as if the ruling had never been made; such an order requires an opportunity to be heard, the period between the ruling and the order is excluded for limitation computations, and a copy of the order must be sent to the applicant, the concerned officer and the jurisdictional officer.