After the moon got free of us, 717 Mya sparked off the Sturtian. There was a hypothesis in 2020 about a "plunge" in sunlight but, I take it, we didn't find evidence that the sun was radiating us much less than usual at the time.
Now they have a different idea - volcanoes. Rather: lack thereof. Since we already had chloroplasts, the rest of the carbon/oxygen balance was volcanoes on the one side, and weathered rock on the other. Canada was doing most of the vulcanism 800-717 Mya (because the moon was squishing us more?). Anyway after that cooled off, the rock kept weathering and then the glaciers came, which added to the albedo.
The new Sturtian equilibrium was a bright shining Earth-sized Enceladus. The volcanoes were bottled up; there might not be weathering anymore but who cares.
That ended 660 Mya, thankfully.
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