If you cut it part of the way through then the top will put out some new roots just above the cut. But I would agree with Lars Kurth and wait to do it unless you have a glass house or other means to keep the temperature and humidity up.
I agree with you Rosie. We are probably picturing the plant differently.
I pictured a long, maybe 4' tall vanda not including the roots at the bottom. If you cut this vanda in half and this vanda were to have 2 to 3 roots above the cut then you would have 2 perfectly happy vandas.
Basically what I gather from her question is that it's a long vanda. How long she doesn't say. Theoretically she can cut it a bunch of times as long as there are a couple of roots and leaves remaining on each cutting.
Hi every one who answered my question. The vanda has a spike now so I will leave until spring. I will keep the lower half as you advised it my get some young plants.