No. He'll pay your mother the full amount under his order of support until mother surrenders the payments. Federal law delegates the court's authority to the mother. She decides whether she gets support and whether she enforces it. She is also empowered to waive arrears.
The way it should be perhaps is that dad files a petition where mom stops support so dad can pay for your community college and perhaps books and transportation. Why should mom get all the money when your upkeep requires way more support your dad may be unwilling to give to your mom.
So dad is stuck under the current order and no court will let him off the hook unless mom agrees to let him off the hook.
What your father is saying is not true. The age of emancipation for the purpose of child support in New York is 21, not 18. You do not need to be attending college full-time to still receive support. Working part-time does not relieve your father of the obligation to pay child support. You would have to be working full time or earning enough money to be self-supporting. "Self-supporting" meaning paying for your own housing and all of your other expenses.
I cannot tell from your post whether your father is currently paying support pursuant to any court order or not. If your father does not have a court order of support and just stops paying what was previously a voluntary amount, your mother would lose support for every month she waited prior to filing a petition for support.
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