Great flounder gigging guide in NightStalker Guide Service!
As for advice, I would try to find some shell up north toward Mesquite Bay this time of year. I think with it being a little cooler this spring, you might have some better luck there since the mud holds the heat. That said, it could be a little spotty because of all the rain, which then fishing farther south toward Port A might be a better bet. Otherwise, farther toward Port A, I'd consider Shamrock, Super Flats, or around Mud Island. I think between those 3 spots, you probably will get on some fish at some point. Let us know how it goes!