They were getting too many returns for 'issues' from overheating. Ie people who don't read instructions etc, and overloading the thing and making things go BTFU. Gee, people not following instructions, say it ain't SO !!! as the Z glances up from it's phone, annoyed at the 2 seconds you just took away from it calibrating it's selfie stick.
It's a thermal cutout that is tripping. Some coffees are more prone to this. For lack of a better way to put it, some coffee's their surfaces are rather rough and they don't loft / move very well, this creates a bit of a back pressure, which keeps the heat down in the unit more, instead of being expelled up into the beans where it is intended, it overheats and shuts down. Overloading causes this as well.
WARNING: Any adjustments you make to the item will void any warranty and potentially create a hazard, if it does catch fire, is a chaffer as an example, it may NOT shut off properly until all the magic smoke is let out of the wires including inside your walls!
With that being said, you can bypass the thermister, or put a higher value one in there so it trips later, or as mentioned, move it away from the side a bit, but do know air is a wonderful insulator, so even a tiny will make a HUGE difference in shut off temp. You may end up melting things in the long run or drying out fan bushings, premature failure etc etc.
What I had to do with my original I roast when it started acting up is twirl it in a roundy roundy motion when roasting to keep the beans moving around, to help air flow thru it until either they smoothed out enough on their own due to the friction of them roasting OR,... more often than not, the roast was done. or B: roast less at a shot, throw half an oz less / an oz less in there and see how that works.
Naturals are fairly bad at being the scruffy beans, due to their processing method, being LESS processing hence are rougher surfaced.
Play around be be careful and always.
NEVER WALK AWAY FROM A ROAST IN PROGRESS E V E R
Aaron