Good question, but I expect it will be treated as a fix or improvement, rather than extra content. So I expect the demo users will be getting the Blackwood updates, and the S1 guys will get the South City ones.
I rekon it might actually be harder to drive than the FOX. This FB02 looks like it will bite you badly when you get it wrong. I will enjoy it though, my favourite car to race at the moment is the FOX. It should make the online racing even closer. Place your bets for what make the next tintop car will be.