Each year around the Christmas holiday, Apple’s App Review team takes a break from reviewing the thousands of apps that pour into the App Store on a typical day. During the break, new apps and app updates are not accepted. This year is no different. According to Apple’s Developer news site:

The busiest season on the App Store is almost here. Make sure your apps are up-to-date and ready for the winter holidays. New apps and app updates will not be accepted December 23 to 27 (Pacific Time), so any releases should be submitted, approved, and scheduled in advance. Other iTunes Connect and developer account features will remain available.