No, sadly the boundaries of IB do not extend south of I10. Here's a link to a map: http://www.mvn.usace.army.mil/recreation/docs/Aerial%20Brochure%20Map.pdf
I had a couple good hunts out there last year, though, as another paddler, I would warn you that it's tougher for us out there. Lots of hunters, long paddles, and very little open water. Most of the open water is closer to I10 (a long paddle). There's some good holes close to the pipeline lauch, but they go fast. And by fast, I mean you would need to be paddling by 4. That said, it's beautiful hunting out there. Worth at least some scouting.
Hey sen me a email an wi will be willing to take y'all out there and show y'all around a lil bit and show y'all some good spots to hunt y'all can get in to by paddling. And with wadders. Lafayetteduckhunter23@yahoo.com
You from montz? I am from laplace. Dude come home on the weekend a few times and hunt salvador wma. We were killin a bunch of ducks at the end of the season out there. I dont know of any really good hunting out by lafayette that is public. Salvador is almost all divers so it doesnt really pay to hunt it until the second split. I hunted in davis pond but some friends i know hunt bayou gauche side and smoked em there too.