“In our judgment the failure of the FTT to take the requirements of reg 201(b)(iv) into account in this way was wrong. The regulation is clear; when he makes his claim the claimant must provide documentary evidence that planning permission has been granted. This can only mean the correct permission, meaning permission relating to the works actually carried out; in that we agree with Mr Brown. As we have said, Mr Patel was not in a position to do that in 2011, since it was not until 2012 that the retrospective permission was granted. The requirements of the regulation are framed in mandatory terms; HMRC are allowed no discretion to accept something less than the prescribed documentation, nor to extend the time limit, and it is equally not open to the FTT or to us to do so. HMRC's appeal must succeed on this ground.”