Had a look yesterday, unfortunately big surf forecast last weekend resulted in missing lowest spring tides.
At Wheal Mexico (Long Rock) the line of flat rod supports is in part visible across the beach, however couldn't quite get on to the rock dry right on low water. At Wherry found the bases of stumps ov vertical timbers presumably parts of one of the bridges leading out to the various shafts.
All these features appear very fresh & devoid of marine growth so I assume are freshly exposed unless anyone can state otherwise. We surveyed the positions at Long Rock but rising tide prevented this at Wherry.