Given that there are still seven demos and one "new" 2011 Roadster still for sale, I don't see how they can stop supporting the Roadster.
BE PART OF IT - The Final Countdown - Page 2
Moreover, they are selling CPO cars with 37-month warranties. So obviously they have to be able to service cars and address the various maladies of car ownership. I have heard nothing suggesting that Tesla will not continue to be help us get our cars repaired to stock. And that includes battery replacement, body parts, and mechanical parts.
As for upgrades, the data tell us we have cause for concern, and particularly any new customization options.
The one notable exception is the rumored pack upgrade. I'm still confident that something will materialize there, given the multiple indications we have gotten over time. It sounds like it will be 2014, though, from Elon's obtuse reference to "something cool."
I also think Tesla is run by smart people who would not like the blowback of bailing on Roadster owners. It isn't the right thing to do and it would leave future car owners of any model worried about the same treatment as tech and models ran their life cycle.
I agree it's a bummer to no longer offer upgrades like a 2.5 front end (glad I got mine when I did!), but I think that we can generally expect continued support to the level of stock repair.