You would have to petition the court for a downward modification. I suggest that you work with the attorney who handled your child support case. If that is not possible (due to expense, can’t locate lawyer, etc.), you can contact NY Division of Child Support Enforcement. They should be able to help you:
I suggest that you file a petition for custody where you and your girlfriend can appear before a Family Court Judge and enter into a consent order there for joint custody. Once that is done you can appear before the support magistrate (on a downward modification petition) and have a consent order entered, which deviates from the child support standards act based upon the amount of time which you spend with your child and the cost you incur during your visitiation.
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