provided that any person aggrieved by the decision as being erroneous in point of law may, within such time as may be limited by rules of court, require the tribunal to state and sign a case for the decision of the court and, where the decision of the Lands Tribunal is given on a review by way of appeal of the previous decision of another person, that person if dissatisfied with the decision Lands Tribunal shall be treated for this purpose as a person aggrieved thereby.