Now we are working on an application release, which should be issued before Christmas Eve. Please let me know till what date we are to send our application release for enrollment in AppStore in order to assuredly get your approvement before Christmas holiday.
Depends on the queue - timing is hard to know, especially when there is no promise it will only take one review to be approved. I would get busy now, and not decide to release to the store until you know it's been approved.
Otherwise, this schedule went out Tuesday...
The busiest season on the App Store is almost here. Make sure your apps are up-to-date and ready for the 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.
With the new App Store on iOS 11, you can let customers know about promotions, upcoming features, and events within your app at any time using the promotional text field. Your app’s promotional text appears at the top of the description and is up to 170 characters long.
Yesterday -- sorry you missed it!
Just kidding, but there are absolutely no guarantees on how long it will take to review an app. You should submit your app as soon as possible to have the best chance of getting it approved before Christmas.