When unarmored and unencumbered, the monk adds his Wisdom bonus (if any) to his AC and his CMD. In addition, a monk gains a +1 bonus to AC and CMD at 4th level. This bonus increases by 1 for every four monk levels thereafter, up to a maximum of +5 at 20th level.
These bonuses to AC apply even against touch attacks or when the monk is flat-footed. He loses these bonuses when he is immobilized or helpless, when he wears any armor, when he carries a shield, or when he carries a medium or heavy load.
At 1st level, an ironskin monk gains a +1 bonus to his natural armor. This bonus stacks with any existing natural armor the ironskin monk already has. At 4th level, and every 4 levels thereafter, this bonus increases by +1.
This ability replaces the monk’s AC bonus ability and the ability to add his Wisdom bonus to his AC.
Does the ironskin monk also lose the bonus to CMD since it's only specifying AC? I'm reading this as RAI and thinking that CMD is nixed as well