Might be about 800 vertical feet?
Now there's a series of chutes/slide paths in this zone. I counted about a half dozen different swaths cleared. When I first heard about it, I assumed it was the other side of the road as there are south facing cliffs there that are so much closer to the road (shadows in this satellite image).
You can see evidence of some past ones to the south too... but I think this was the biggest rock slide in quite some time, at least since I came up here to UVM back in the early 2000s there's been nothing remotely close to this.
They do highly suspect the weather playing a big role... before the record heat, there was still snow high up there and water inside the rocks was almost certainly still frozen solid. Then it hits 85F rapidly before dropping back to freezing this morning with a period of heavy rain yesterday and the day before with thunderstorms. I'm no geologist but the idea seems to make sense that rapid temperature swings could do that, like frost heaves in our roadways.