The double A on the debt means nothing. All the monolines have had AA rated in their capital structure for years. It's the AAA corporate rating, which Fitchc affirms will be made stable with a successful offering of these surplus notes, that counts.
If you look at the pre-market there is no significant volume yet, but the price has risen steadily from 15.25 to 15.43 over the last 15 minutes. Once the market digests this, look out for a major pop.