I've put in a CSA claim to force ex's hand as he hasn't stepped up to do a 50/50 childcare arrangement he said he would. I have based the claim on the sporadic overnights he has done to date. I was wondering how it works if the payment request provoke him to doing his bit. Does he have to prove himself over a certain period before they lower his payments? Can he just say he will do more and then renege on it and leave me back at square one?