DP (don’t live together) tested positive a few weeks ago using his kids’ ones from school. Don’t think he registered it anywhere? He’s then been using them after the 10 day quarantine period to test whether he’s now negative and can see people again. Was still showing positive after 12 days but don’t know how accurate they are anyway. Don’t suppose he’s logging the negatives either.
He should have had a PCR test (which would have been logged) to confirm the positive lateral flow test.
You're also recommended not to continue to use LFDs within 90 days of a positive test as they may continue to show a positive result ,so his plan to see if he's now negative is not going to work ...