If you are currently in beta there is no issue with registering your pre-order key now.
If you are having an issue with registering your key (you get a message saying you consumed the key without ever having consumed it) please read these instructions: http://forums.vanguardsoh.com/showthread.php?t=105037
You will be able to play the live version for a limited time with your pre-order key. Any time after the 30th will be based on shipping information and distribution. We encourage you to register your retail key as soon as you can to avoid any disruption of service while you're playing