Yellow ray in a STO individual

[βαθμιαίος]

The part that is still evading me is particularly the concept Zen spoke about in an earlier post...which Ra mentions here:

39.10
When green ray has been activated we find the third primary ray being able to begin potentiation.

What is the difference between yellow ray prior to activation, having the potential for activation and so being in "potentiation," and what Ra speaks about here?

Is the difference simply that, now that green has been activated, the activation of yellow is now able to be determined by green ray activity? Yellow ray would really be going back into potentiation, just this time with a different type of potential?

I don't believe that quote has to do with yellow ray. The third primary ray is blue ray:

41.25 Questioner: Why are the red, yellow, and blue energy centers called primary centers? I think from previous material I understand this, but is there some tracing of these primary colors back to intelligent infinity more profound than what you have given us?

Ra: I am Ra. We cannot say what may seem profound to an entity. The red, yellow, and blue rays are primary because they signify activity of a primary nature.