I will offer my annual rant that this is all about the advertisers. The listeners don't count here. Stations switch to holiday music in mid-November because it makes them money. Case closed. If these stations cared about their listeners, they would play holiday music during the week between Christmas and New Year's, when I think people would want to hear such music as they enjoy time off from work and attend holiday parties. But there's no money to be made then because the Christmas shopping season is over. Nobody will ever convince me that listeners would prefer hearing holiday music on November 15th rather than on December 26th. It's all about the money.