Why do light layers correspond to rendering layer mask? (HDRP)

Say, I have a reflection probe and want it to affect only a certain object. So, I set its light layer to a specific layer that I can rename however I want. But to assign an object to this layer I must go to its mesh renderer component and pick a layer from the rendering layer mask dropdown, which contains (!) a completely different list of layers.

Just to illustrate how the described setup works:

This is the layer selection on the probe's side


This is the corresponding layer on the object's side:


I figured this out only because of the fact that these two layers come second in their respective lists. But it's really counter-intuitive. Why do we have the correspondence between different layer systems and why one of them can be renamed while the other can not?

And an off-topic question: when can we expect the next beta release?

 

Bump.