Mid-year introduction, but I don't recall the date I first saw one, which would of course be sometime after production started. I visited Dodge & Plymouth dealerships on a weekly basis back then.

Remember, SCHEDULED production date isn't necessarily the ACTUAL production date, which begs the question: Maybe some were scheduled before being approved/authorized and then actually built? More likely it's a stamping error.

It would seem prudent to have cars in the pipeline by the time a show car was displayed, to take advantage of demand, but everything I've ever heard or read (to take my memory out of the equation) says the Road Runner came 1st, its success surprised Chrysler, and then Dodge wanted in on the game.