It's probably one option floating around the table but those who have been in the industry long enough know that things can change in an instant.
Even if a commitment was made to manufacture the commodore till 2020 it could still get shit canned. The GFC saw many makes and models disappear through forced rationalization, some which people thought would have been safe.
I saw an article a few months ago that talked about the commodore being built offshore to reduce costs, what Wonky heard may just mean it won't be produced here but the model will still be around. If successful in the US they could always build there to support local industry, similar to what happened with the Cruze in Oz.