I also had the same issue, where somehow both of my EA 20 digit codes were applied to my one account rather than my wife's, even though I'm sure I logged into her account. (I did it on the same computer so that may have been the problem.) I've been trying to get through to support, hoping they can remove one of the EA codes so I can apply it to the correct account.
From what I understand, if this isn't possible, we should both be able to play under my account and would both have early access, right?