First, any time your income changes by 20% or more, you need to file a motion to modify your child support to get it reduced. You cannot delay in doing so, as modifications can only be retroactive to the date you filed your motion -- not to when the change in income actually occurred. Second, the ONLY way to get your arrears reduced is via the agreement of the mother, and then only if these are funds owed to her and not to the state for welfare repayment. Child support matters are one of the more clear cut areas of the law, and there is virtually no wiggle room.
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