The Missing Five
GM numbered the Collector Editions 001 to 940, but built 935. Numbers 246 to 250 were scheduled with the cars around them, which were built on 14 December 2016, and never built. Each of the five orders was built two months later under a new number and VIN, with exactly the same equipment.
How we know
In 2017 a GM contact told the registry that the five numbers were scheduled but not built when scheduled, and that their orders were built later. GM's order data then made the match: each original order's option codes are identical, code for code, to one later car's, and no other car matches. All five are automatic Z07 coupes for US dealers, built within ten days of each other in February 2017.
The five numbers stay empty: no car carries a plaque from 246 to 250. A plaque with one of those numbers is not a production Collector Edition. Never Built, in How the Registry Works.