Since the 2 differ only in the position of one double-bond, I'm almost certain that ALL D9 extracts will contain D8. Certainly it naturally occurs in the plant as a minor constituent of the large mixture nature endows the plant with.
The USA is a mystery to me. Nowhere else would even attempt to control a compound that is legal the moment you inch over an invisible, unwatched, uncontrolled boarder.
But then the UK is even worse. Economy in tatters, inflation through the roof and EVEN official Home Office estimates suggest it would produce £4.7 billion/annum in duty and taxation and create 6500 jobs. It's merely that the elderly (who are the MOST likely to vote) were brought up when 'drugs' were the byword for evil and they swallowed the whole lie in a single bite.
I'm guessing that in 10-12 years time even the elderly will recognise that cannabis is less harmful than alcohol and tobacco, that it isn't a 'gateway drug' (tobacco has repeatedly shown to be the largest gateway drug by far) and that if people have to resort to criminals to acquire a smoke, they are much more likely to be offered much more hazardous drugs.
Sorry to whine but it's going to be MY generation that recognizes this and will only matter when we start drawing our pensions,