Unreal Engine 4.25 Preview

let’s talk about light channels!
4.25 Preview 6

admittedly i have a lot of lights in my scene [is there a limit per light channel or something, that could explain the below issue?]
The Issue:
I have a Rect light on channel 01 on and a ground plane as well as a glass windscreen which has NO light channel attributed to it. is my thinking wrong but if it does not have light Channel 01 set as its flag it should not receive the light emmited from the light source on Ch 1?

No matter what light channel I put my lightsource on [and same for the windscreen] the rectangulat light still hits the windscreen. Only by turning off the light source does the reflection
go…