SACM20090 - Appendix 1: Old Error or Mistake Relief: Determination by Board
From 1 April 2010, it is not possible to make a claim for the old error or mistake relief for any period. The relief is replaced by overpayment relief, see SACM12000+. You will only need the guidance in SACM Appendix 1 if you are dealing with a claim made before 1 April 2010.
The determination of the Board on an application submitted to them is notified direct to the taxpayer. If the application is refused, the taxpayer is at the same time advised of his right of appeal to the tribunal.