I have no idea mate, Dredger was still in the harbour last night, so guessing they're still at it...
I Don't really know what this means for the mark either, hopefully not too much, but if they're messing up the sea bed inside the harbour maybe it'll increase feeding for a while? Of course the other option is it'll just destroy whatever the fish are coming into the harbour for and the fishing will be terrible for a while.
Guess the only way to know is to let it settle for a couple of days then go down and try it.
Will keep you posted as to when the dredging stops mate.