I am participating in one of the Oxford Vaccine Trials and each week I have to do a home test for Covid-19. I take the swabs and post off the kit to be analyzed. I have been doing this for a while. Initially test results came back in 2 to 3 days. As we got into December /January the time scale was nearly a week. The lab had a lot of work. Now I got the results for a test I did and posted yesterday at 11.00am this morning. I doubt results can be much quicker than that. Another sign that the situation is getting better!