Hi Dave This is definitely bronze, I guess I will grind or sand back epoxy barrier coat until I find good adheasion and reapply barrier coat.
It's hard to tell from the photos, however, I doubt that skeg is bronze. It sort of looks like stained gelcoat. Back in the day when this boat was built coal tar epoxy was often used as a barrier coat. The staining looks a bit like it might be from the coal tar.And I suspect the skeg is fiberglass, with bronze ”hinges”.