Well I can’t tell you if the drug test thing is true but THC definitely doesn’t turn into THC-A in the gut lol. THC-A is actually inactive mostly via oral or insufflation (yes I’ve snorted pure THC-A for science) and needs to be converted to THC via decaroxylation before it’ll get ya high.
When THC is eaten Delta 11 THC is one of the major metabolites, this is why oral cannabis feels different.
My guess if we’re talking oral swab drug tests, is that those pick up residual THC from the smoke. This is why they only detect in the range of hours instead of days. If they could detect THC in the blood via saliva you’d be fucked for a month.
So while I believe the rumor it’s not due to THC-A or Delta 11 but the ROA and how these swabs detect.
-GC