Chevrolet Zone Courtesy Cars

[ohhawk]

Can someone tell me (with some certainty) if these cars were always produced prior to fullfilling customer orders and dealer stock orders at the start of model year or could they be produced throughout the year? The only two I've seen noted on buildsheets have thus far been at the very start of a production year so just wondering.

Also, any further explanation on the prime purpose of these courtesy cars would be welcomed........thanks.