Sorry g.ordon I didn't mean to imply there were no fish, I would imagine there is plenty of rag and little crustaceans in the mud further up past the bridges.
I too thought the area you described would be good for flatties and bass.
Don't really know too much about seasons up here but from past experience in Swansea this is the season flatties slow down to a stop and it's 2 months early for bass and ages before mullet.