I just did that this past Friday, as I surpassed the $500 limit. It only took about 20 hours for mine to change from "Pending" to "Verified".
Very short time for mine. One caveat to all - if you change anything at all, including email address, you have to do it again. Odd, but then, good security. If you have any difficulties, I found an email to be answered almost instantly with great courtesy and assistance.