All servers currently used are being converted to TBC servers

All servers currently used are being converted to TBC servers. The new servers will be available. Vanilla versions of these servers. You can choose to activating the character either the Vanilla or TBC version. If you'd like to activate the same character on both the servers, you will have to pay.

Edit Note: This article came from Blizz. "On patch day, you'll be able to launch the Battle.net desktop application and select which game you'd like play--Burning Crusade Classic or WoW Classic. Your existing characters will appear on both game types under your old realm name/s. When you have chosen a game, choose a character that you would like to play and then confirm. You can use an optional paid service to gain access to the cloned character from both game types if you decide to play your character in both. Then all you need to do is login as usual and then play."If you want to know more,you can visite mywowgold.com/

Because the copy is finished prior to release Yes. Classic contains all the characters, therefore there is no delay for copying when you select Classic. TBC could cause downtime, due to the fact that it isn't immediately. It may also result in a lot more characters being copied simultaneously. This could lead to the system being unable to function properly.