"Crash7800 (EA Communiy manager) stated in reddit "Your call, I guess, as to if it's worth the risk. Personally, I'd wait. Definitely won't work for multiplayer, and if it did all you'd be doing would be creating a needless headache for our network staff."
If you do manage to bypass or risk to play muliplayer, just know that you would only be able to play multiplayer on the Asian servers . Expect to have 300+ping and joining into clogged up servers. There are still question going around the web whether or not this is safe. The safest way in doing this, would be to see the safety confirmation of the people who have done this and have everything running like I should (everything is working) after the Korean version has been lunched.
If you have this already or jumped into do this without knowing what the risk are or what they could be. Don't worry about the ban hammer, It's has been publicly announced that EA won't ban for this, for there is no legit reason to do so. This VPN program can be an alternative proxy and privacy protection, so EA can't argue to apply the ban hammer. I am sorry, but I do not know how reverse this once you have done it. My one guess would be to delete BF3 and all its contents like its reg and download. If this has worked let us know.
EA has also stated that this is not illegal, it's just isn't very nice. ( meaning this is a go, but it's only a go on your own risk.) "