I have the same issue, due to time zone differences I can only be around for the last hour or so of chat support being open so I haven't been able to get in.
Also need to change my EU key for NA.
I put in an email support ticket before I tried chat, but still no response from that.
I understand the large amounts of traffic, but at this point my early access will run out and I won't have the game on my account when I pre-ordered.