After taking a few pictures I stood it up again.
We'll have to bury the legs for the next wind storm. They were buried before yesterday, but not at the moment. Even though it's lived through plenty of strong winds since it's been outside, this was the first time it's blown over.
Before I stood it up, I got a good look at the dirt at the bottom of the piece. It appears to be only at the bottom, on the surface, so the coating I put on the fabric is helpful. I think the "damage" is mild after being outside for this length of time, including after it was buried in snow for 2-3 months. This pleases me a lot.