Upon the hearing of an appeal, the appellant shall not be restricted to the grounds stated in his notice of objection or appeal and the authority against whose act or decision the appeal is brought shall not be restricted to the reasons previously given for such act or decision (if any); but where any new ground or matter is raised on the appeal the Tribunal shall, by adjournment or otherwise, ensure that the parties and any other person entitled to be heard have a reasonable opportunity of properly considering and replying to that ground or matter.