Thank you for your interest in the game, and taking the time to ask your question!
All who are accepted, who have the Windows Launcher, should be able to have their files patched to the Limited Access Release Build. All others would need to download a fresh client for their respective Operating Systems.
However, due to the fact that the Limited Access Release is different from earlier OSE's, it is possible that everyone who is accepted must download a new Client to play the game.
All specifics of that sort will come in time, so be sure keep track of the website!