I'm sorry if I didn't read the original post right but:
You were number 4 of 4 and there were 3 SS's in front of you.
Dealer gets allocated an SS (I don't get the V8 or V6 since that is all Camaro's) and places one of the earlier SS's in front of yours. That's OK.
Or, the 3 SS's were already sold and delivered and he had an SS behind you and bumped you. Not cool.
I will assume it's the second scenario.