Subtle and cumulative - a rock pile site in use today

I noticed this place a few years ago (see here) and, from the fresh dirt over the snow, it was clear the place is in use with new piles being added. But I suspect there might also have been older structures already in place. I was thinking about this possible accumulation at sites when I stumbled back into this place.Since it is now summer, I could see more than last time. The whole cliff face incorporates flat rocks that have been pulled out of their natural seating so as to form a shadow and an overhang. These are easy to see from below, but probably not from above. Does that suggest the site would have been used from below?Some of the rocks are big enough that a crowbar or some other lever could have been needed to move the rocks.