That's not how it works - if the model is currently being made, then it has to be re-labeled with the new system. The only instance when the stores are allowed to use the old label is if they literally still have old stock, but it should disappear from shelves pretty quickly.
As the label deadline is approaching, it would seem a large advantage to make an extra year’s worth of product and stuff the channel. Retailers would be happy to participate as they’d now have a higher margin “A rated” appliance to offer.