It’s around the middle somewhere but it really shouldn’t matter as you don’t really wanna be in more than 10’ of water. Don’t think that you need to be out in the middle, you don’t. Find a bay and tuck in on top of the break. The N/S boundary is interesting. I’ve always just stayed on the inside of the furthest South Island outside Bay City. Don’t know about the south end, never bothered to hunt it.
You cannot hunt both states at the same time, even with both licenses. I have email proof from the DNR that it’s illegal.
You need to be careful, specially in high winds (Sunday). Be sure to have a tender that’s actually WATCHING you and not wetting a line…layouts get sketch quickly. Make sure you’re anchored.