Hello
We had a figure worked out by the CMS when my partner and I were first living apart but we decided to try again. When we split for good we went by that figure which I had to constantly ask for.
When my ex set up a monthly payment it was lower as he decided to do the calculation himself as he now has our child a couple of nights a week. I have no problems with this but it is done off his basic salary when he does a lot of overtime.
For the sake of not straining relations I haven't mentioned anything, but he is never away from work at the moment and I feel like he is begrudging passing this on to his child.