Probably due to the fact that the supplier filed for bankruptcy earlier this month, GM sent a note to its dealers saying that it has a "wheel supply" problem with the wheels for the Corvette, and that dealers would have to change orders based on availability. GM has found a new supplier, evidently, but the supplier can't do polished wheels, it can only do silver painted wheels -- and the chrome wheels that have everybody so excited are being pushed back to late spring. How this will affect the Z06 is still unknown.
Long story short -- GM can't get its wheels, which messes up production schedules and creates a big headache for dealers who have to go back and change orders, with apparently uncertain options for replacement. Funny how the nuts and bolts of manufacturing can be a real buzzkill, eh?