https://www.gov.uk/government/publications/covid-19-stay-at-home-guidance/stay-at-home-guidance-for-households-with-possible-coronavirus-covid-19-infection#SymptomsPositiveTest

Update to Government Guidance, 30^th December 2021. The self-isolation advice for people with coronavirus (COVID-19) has changed. It is now possible to end self-isolation after 7 days, following 2 negative LFD tests taken 24 hours apart. The first LFD test should not be taken before the sixth day.