It is almost midnight here in the UK as of writing this.
I've been getting error 601'd with the same card I used to pay (without any issue whatsoever) my FFXI account. My other CC gets the same result. I had the same issue yesterday but hoped this was some kind of fluke. So, I queued into the chat support website and waited for two hours to try to sort this out.
This is the result of my patience. I was watching the screen like a hawk when it was down to me being the second person in the queue:
Chat Close A connection to the Chat Server has been established successfully.
Status: Canceled
Searching for an available agent
You have been re-queued.
You have left the queue. If you still need assistance please try back later.
You have left the queue. We hope you have found what you were looking for.
There are no agents available to chat with you right now. Please try again later.
There are no agents available to chat with you right now. Please try again later.