they are allelic, all the genes involved.

http://www.owalreptiles.com/complexes.php

so, onyx is black pastel het red axanthic. when you breed that to a normal, you get 50% black pastel 50% het red axanthic. now you throw in cinnamon.

should be:
25% cinnamon black pastel
http://www.worldofballpythons.com/mo...stel-cinnamon/
25% cinnamon het red axanthic
http://www.worldofballpythons.com/mo...-red-axanthic/
25% black pastel
25% het red axanthic

the genetic wizard at world of ball pythons is wrong in this case. It doesnt take the gene complex into account, for example, in this pairing you cannot get normals, and a "black pastel cinnamon het red axanthic" is impossible. its like breeding mystic mojave to lesser, just that the genetic wizard finally gets the potion stuff right ^^

very good pairing, good luck! black pastel cinnamon is awesome, and i suspect it does not have the issues that a super black pastel or a super cinnamon sometimes has, you know, duckbill. and cinnamon het red axanthic is also nice.