I didn't make it that far down the FAQs! :-(
Since they haven't provided any guidelines as to what purchased in BC means, and the Tesla adapter is only sold online through Tesla, I just can't see them causing us any grief, particularly after their "good news!" tweet. I just don't think they want to be inundated with eBay and Craigslist buys, people using Amazon (or other stores) in the USA, etc., etc. I'd be willing to bet a Costco.ca buy is fine, as would be a direct sale from Amazon.ca (for example). But, particularly in the case of Tesla, there's nowhere else to buy from but Tesla (Canada).