I'm confused on what this is asking.
If you've already started hunting rayquaza, the shiny odds for the legends and UBs are just the base normal and shiny charm odds, those don't change with distance like the regular wormhole Pokemon.
If you're asking about the odds of finding a wormhole with rayquaza, then there is a couple of factors needed to be known, like the number of rings the wormhole has/had and the number of legendaries you've caught out of the red wormhole.
Based on the word currently though, I'm guessing you're in the first situation I said where you think the shiny odds change for the legends and UBs. Can you clarify if I'm correct?
