Not to defend dealers but... Ad space is typically purchased in blocks, so it is conceivable that the ad is still being run even though promotion is over. Alternatively it's a premature ad.
Also, dealerships are slow to update their sites.
At least some of the dealers here have the ability to change ads on a daily basis. There was one Chevy dealer that ran date specific ads that changed every day for a week. Its my understanding that they buy the block, but can change what they broadcast willy nilly. So lets assume the promotion is over - go back to just advertising how awesome your dealer is, rather than a deal that doesn't exist. Or, time your deals to coincide with your advertising blocks. Those are dealer defenses but excuses.
Not an excuse. Update the site to reflect the advertised deals BEFORE the advertisement goes live. I can't be the only one getting pissed off by these practices.
None of their cars are terribly handsome and they've all but killed the Renaultsport line up that made them awesome to me throughout the previous decade.