It actually becomes a very grey area in terms of private sales though, as condition, colour or even location in the country could potentially have more of an impact on resale value. Private buyers generally don't want to travel the length of the country so look closer to home.
My guess is that there'll be loads of S-Lines on the market (particularly in Daytona!). However, if someone is looking for an A3 and doesn't want a black interior, the scarcity of SE and Sport cars in certain areas of the country could even mean they command a bit of a premium! Only time will tell.