I use a bio stat, and a lot of aspen. Odd you ask about this as I had a major issue of my cage temps going way up.
I fed all my snakes, most rather new and almost ALL upchucked.
I actually checked temps in a cage and it was in the 90's!
I got a digital read up with a probe in 1 cage, reset biostat.
All snakes have ate at least one and kept food down. PHeeeeeeew!
But I have had to keep readjusting my biostat to keep it at the temps I want? I'm still not sure is a stat issue or where I have the stat prop. But clearly it is worth a stat or a thermometer with a read out as a secondary read on temps.
Also like when I had a lot of ball pythons, I see some corns sitting on the warm end at 85-86, and some that love the cooler end. I think long enough tubs, or tanks to allow a good gradient temp pattern is critical is all cages are on one stat.

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Thanks for reading.
Big Tom
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