Actually, for a player who currently plays on an APAC server, there is no effect. You can still play your current characters and even make new ones! What the lock does is stop players who do not have characters on APAC servers at all, from making new ones.
Again, if you're an APAC player who plays on an APAC server, this has no effect on your ability to play.
So when are the APAC servers being turned off ? I'd like to stay on my server until the last possible minute then decide if I want to continue with the game.