I have a theory regarding plants such sibuyanensis, ventricosa, argentii or any other plant that comes from the philippines. If the plant is labelled a lowland or highland, well, don't take the description so serious. My ventricosa loves warm weather and it gives the best pitchers in warm weather.
Furthermore, truncata lowland ( also from the philippines) can tolerate cold nights as long as the temperature does not go below 40 F. This is very unusual because the true lowlands such as rafflesiana or ampullaria or bicalcarata will dry up completely in these temperatures. Furthermore, i would not be surprised if truncata highland can tolerate warm weather as well.
So far all the highlands and lowlands from the philippines like intermediate to conditions. Please correct me if there is one that is strictly a highland or lowland and come from the philippines.
The reason why i am mentioning this is because, Tobaica even though not from the philippines, but from lake toba is usually mislabelled as a highland when it behaves more like a intermediate-lowland to me. it has not pitchered yet since early this year, so i hope that by summer, it would start to pitcher. (i am growing 80% of my stock outdoors) Thanks