Testing after having covid

[Waves12345]

I was told by T&T a PCR is likely to read positive up to 90 days after having covid, is this the same with LFTs? I’ve been regularly testing all of us but want to check I’m right not to use them for that time period now? My son is on day 8 and we just did a LF and it shows up positive still, but I’m presuming once he’s completed the 10 days he is no longer able to pass it on? Thanks

Yes, it's the same with LFTs. You're not supposed to do any tests for 90 days. Your son can go out after 10 days as long as he doesn't still have a temperature or D&V.