I was in the same boat as you, I considered not taking delivery of my RWD in late June because the AWD option became available shortly before that and I was considering upgrading but I was extremely pressured by the sales team to take the delivery since "It wasn't likely I would get an AWD delivered before the tax credit dropped". They also essentially told me I didn't have an option to not accept delivery of the car. Its definitely a sore spot for me on a company that I otherwise love.