Rare indeed!Honestly, I'm not sure, ask FP and see what they say, there are some very knowledgeable members on here about that subject, hopefully they chime in. I never trust salesmen, a good one is very rare!
From experience with the 21 guys, your order was considered "locked in" approx 2 week from build date and no changes were allowed. More importantly, it all depended on your dealer as some would gladly make the change and some were a$$ holes...and you got what you ordered.If you don’t have a vin, you should be able to make changes