The exempt amount will be shown on the Additional Information pages (page Ai2, box ASE9). Any amount greater than the exemption will be shown in box ASE5 on the same page.
HMRC Special 18 applies where a taxpayer has more than one lump sum from different employers. It allows the taxpayer to claim up to the £30,000 exemption for each employer. However, box ASE9 only allows amounts equal to or lower than £30,000. As a workaround, Personal, Business and Trust Tax leaves box ASE9 empty and adds the number of lump sums and amount of the exemption to FIN19 on page TR7 of the main tax return.