Apple released a note saying that the iTunes Connect section will be temporarily shut down from Thursday, December 22 to Thursday, December 29 for the winter holidays and during this shutdown, the following functionality will be unavailable, Access to iTunes Connect, The delivery of any apps or updates, Additionally, the following will be delayed:
Releases scheduled to appear on the App Store for the first time and Pricing changes scheduled through the interval pricing system in iTunes Connect.

“We strongly recommend that you do not schedule pricing changes through the interval pricing system in iTunes Connect that would take effect from December 22 through December 29. Pricing changes scheduled to take effect during this date range will not be reflected in the App Store and the app will become unavailable for purchase.
We also recommend that you do not schedule any apps to go live during the shutdown. Releases scheduled with a sales start date between these dates will not go live until after the shutdown.

Regards,

The App Store team”