I did three roasts after reading those messages last week, with no-load
voltage at 130, and then dropping to 110 at the beginning of first crack.
I had no problems with it and it did seem to finish my FC roasts about a
minute earlier than without the Variac.
It certainly didn't do an automatic eject - I can only expect that would
happen if the temperature sensor thinks the internal temp is too high.
Are you using a thermometer probe and if so, what did it indicate at the
time it ejected?