My plan exactly actually! Did you have an open bite too? Riley model is 11-13mm posterior airway space (PAS) so surgeon advanced to hit the top end of that spectrum. Over advancement causes lateral wall collapse but another philosophy is just do 10mm cause more is better. Not my philosophy but in most cases people are so deficient that the maximum is the same anyway. There's supposed to be a newer model that avoids some lateral wall collapse, I don't know what it is but I'm curious if anyone finds it.