Year ended 5 April 2023 will be the transitional year for when the new basis periods come into effect from 2023. More than 12 months of profits could be taxable in 2022/23 if you do not have a 31 March or 5 April year end. If you are a sole trader or partnership, consider what impact the transition rules will have on you and whether you might benefit from changing your accounting year end sooner to 31 March 2022 so that the extra tax might be mitigated because of the inclusion of reduced profits due to Covid.