The United States Postal Service is delivering a record amount of mail for the holidays. If you are trying to send a letter or package, there are a few dates you need to know. “We’re celebrating a milestone delivery,” Mark Inglett, USPS spokesman, said. “The Postal Service is anticipating it’s two billionth delivery today for holiday cards, letters, and packages, and we’re really excited about it.” Neither rain nor sleet nor snow, or, in Monday’s case, temperatures in the 20s, will stop the Unit