Actually, this 2010 coupe was built in the middle of the year... intermingled within the 2009's... WELL before the last Solstices left the line.
There's another post somewhere here in regards to the last coupe (which, I believe was the 2nd-to-last vehicle off the assembly line in Wilmington... #1152, and was a 2009 MY), and the last vehicle of all... a 2009 convert. (Was it grey or silver? I don't remember... if someone remembers that post, can you provide a link to it?)
Yeah, I'm sure people will be making that mistake (no doubt intentionally if they are the one selling the car) until the end of time. These cars aren't all that special - it was simply a case of taking some 2009 sample cars and trying out some ideas they had for the next model year, assuming that there was going to be a next model year - new colours etc.
And you can't even go for the last serial number necessarily being the last coupe - take a quick look at the factory records. The last serial number is listed as leaving the factory on Aug. 7, 2009. That wasn't the last car by any means to leave the factory (there were a ton of others noted as leaving that day, a small clutch left on Aug. 20 - 949, 978 etc., but others were as late as Sept 9 - #1131, 1087, etc, )
Face it, they aren't unique if the just happened to roll out of the doors last, but that doesn't stop people from paying more for the 'Last One'. The numerologists will opt for the last/highest serial numbers, the simple minded will go for the 2010 'because they HAVE to be last, right (even though they weren't, but they are dazzled by that year number and don't look any further) and the discerning collector may find out what the actual serial number of the very last coupe to roll through the doors was.
Anyone know what the last one out the door was?
And then of course you have to go through the same process for the last Sky, Solstice convert and Daewoo (well, that last one might not have as much interest to collectors) to roll out of the factory.