BB you are correct.
In NY , my brothers X Petitioned for CS modification every time she got wind , he gained some sort of income , or yearly pay increase.
Finally after the 3rd or 4th time , he obtained a Lawyer.
The Judge flat out told her , just because he gets an increase in pay each year ,or tax return, or whatever , doesn't mean you're entitled to it .
So, before you play that game , make dam sure , he gets enough of an increase to have CS modified , and that doesn't mean every 3 , 4 , 6 , 12 months .