“45.(1) On receiving an application for permission to appeal the Upper Tribunal may review the decision in accordance with rule 46 (review of a decision), but may only do so if – (a). when making the decision the Upper Tribunal overlooked a legislative provision or binding authority which could have had a material effect on the decision; or (b). since the Upper Tribunal’s decision, a court has made a decision which is binding on the Upper Tribunal and which, had it been made before the Upper Tribunal’s decision, could have had a material effect on the decision.”