Same deal here in my state: child support is all formulaic. Good that you're not fooling yourself about why your STBX is delaying. But I'm sorry for you that it's happening. I think until I'm actually moved out it will continue to feel like a bad dream.
Speaking of parents ... I just dropped a bomb on my Mom w/ the news of our divorce. She's old school, just loves our kids to death, and didn't know at all that we were having trouble. She will be devastated.
Me: 50, MLC/WW 45 Young kids Nov 2015: BD1 Apr 2016: BD2 Jan 2017: W filed Feb 2017: D final