Using the temporary pose space state behavior on an avatar can cause inconsistent and buggy behavior for the "upright" parameter on an avatar. Using the same animation for the pose I have had the upright parameter sometimes be stuck always reading 1, and sometimes if you are physically close to your playspace floor and are in sit mode (forcing your upright parameter to 1) enabling the temporary pose space will forcibly reset your upright parameter to reflect your position in the pose space. Either way it does not accurately reflect how upright you are visually in game (how far away your head is from the floor) and causes issues with any system relying on this parameter. If this is an intended feature there is no documentation on it that I could find anywhere, neither official vrchat documentation or unofficial. This should either be fixed or properly documented in the vrchat creator docs so that creators are aware of the issues temporary pose space may cause and how to potentially fix/avoid them.