From Monday, December 22, through Monday, December 29, 2014, iTunes Connect, Application Loader, and iTunes Connect for iOS will be unavailable.
During this time, you will not be able to submit new apps, app updates, or In-App Purchases. You also will not be able to access iTunes Connect or make changes to TestFlight Beta Testing. You can schedule an app release or price changes to take place between December 22 and December 29. Just make sure that your changes are scheduled, submitted, and approved by December 18, to ensure your app remains available during this busy period.
Users who are currently testing or invited to test your prerelease apps with TestFlight Beta Testing will not be affected.