Cura 3.3.1 is displaying expected filament usage incorrectly for some models, but not for others. In erroneous displays it is showing extruder 1 and 2 filaments the wrong way round, ie extruder 2 then extruder 1. See the screen grab - the model prints in orange PLA using 1.47m of orange PLA and 0.24m of PVA support from extruder 2.
I have attached the stl file, which is generated from Fusion 360. The actual print is fine.
Some stl files show this oddity, but others have the extruder filament usage the expected way round, ie extruder 1 then extruder 2.
Closed screw bevel bearing block.stl