visible to reflection/refraction problem

[Numse]

I found a problem on a testrender of an old carmodel. I have planes around the car for reflections. In the objects properties I have turned of everything except visible to reflection/refraction but it still shows in render. Is it because of the GI? Hope you can help.

Here is the testrender. The plane isn´t visible but you can see it anyway because of different lighting behind it and in front of it. I used only one Vraylight right above the car and GI.