“Applications for extensions of time limits of various kinds are commonplace and the approach to be adopted is well established. As a general rule, when a court or tribunal is asked to extend a relevant time limit, the court of tribunal asks itself the following questions: (1) what is the purpose of the time limit? (2) how long was the delay? (3) is there a good explanation for the delay? (4) what will be the consequences for the parties of an extension of time? and (5) what will be the consequences for the parties of a refusal to extend time? The court or tribunal then makes its decision in the light of the answers to those questions.”
“41 It seems to us that the time limit of 30 days for a taxpayer to make an appeal is to provide taxpayers, as those liable to tax and, HMRC, as the enforcer of the payment of taxes, with certainty as to the “cut off” point when the amount of tax or penalties asserted by HMRC to be due as regards a particular matter or period becomes certain and final. In specifying a period of 30 days Parliament has set down what it regards as sufficient time fort a taxpayer to consider whether he wishes to dispute a tax assessment or penalty determination and if so make an appeal. The taxpayer is required to act promptly if he wishes to make an appeal thereby providing efficiency in the conduct of the dispute (should there be an appeal) or finality should there be no appeal. 42. On that basis we would not regard it as a matter of routine for the tribunal to allow an appeal to be made outside the normal time limits. The starting point must be that the 30 day time should usually be adhered to. Otherwise the purpose of the provision of the time limit would be undermined. There would be little incentive for taxpayers to comply with the time limit and the lack of certainty and finality would potentially cause difficulties with the conduct of resulting disputes and burdensome administrative and enforcement issues fort HMRC. Therefore, the tribunal can permit a late appeal only, as set out in Data Select . If it is satisfied that on balancing all relevant factors (the length of the delay, the reason for the delay and the effects on the parties of granting or not granting the application for the late appeal), it would be unjust and unfair not to do so.”