Yes they should be able to narrow down what type of CAH it is.  Generally the milder type of CAH don’t usually have the salt wasting aspect from what I can gather.  Sometimes CAH is so mild that it may not be diagnosed until adulthood so that would give you a rough idea of how mild the enzyme defect can be perhaps.  Other times it may be diagnosed around aged 2 years and up.

They will soon find out what type it is and be able to determine whether it needs treatment or not if it is CAH at all.  I guess they must be getting a little more advanced and able to even determine it from preemie blood samples now somehow--even though they must be somewhat higher than a newborns I guess there is a limit to what the 17 OHP should be in Preemie’s also?  I can’t see that they would have started treatment unless they really felt there  was a strong possibility it could be CAH. I.e. your and your wife having the gene AND elevated levels equals what everyone has said---common sense to treat until things can better be determined.