More details can be found here
‘Confirmatory PCR tests following a positive lateral flow device (LFD) test result are to be temporarily suspended from Tuesday 11 January. This will mean that anyone who receives a positive LFD test result will be required to self-isolate immediately and will not be required to take a confirmatory PCR test.
In line with the reduced self-isolation approach announced on 22 December, anyone who tests positive will be able to leave self-isolation 7 days after the date of their initial positive test if they receive 2 negative LFD results, 24 hours apart, on days 6 and 7.‘