Oh, here's the plywood being used.
It's form board and very resistant to being in the weather as is. First ran across it about 25 years ago.
After being discarded on a jobsite, I brought it home and put it on the walkway to the dock. I believe it lasted another 15 years till we redid the walkway.
And the tell-tale signs of being formboard is the orange paint on the outer edges.
