If you have a support order, agreed or non-agreed, the court will enforce it. If he is behind in his support and considering the age of the child, it is unlikely that he would be given custody. In fact, he could go to jail for not paying.
When there isn't an agreement, the OAG sets the case for hearing and asks the associate judge to make their proposed agreement an order. You will get notice. You should get a lawyer to rebuff his efforts to get joint physical custody. The OAG does not represent you and although they may be advocating your interests on child support they have no duty to be on your side on any issue. Look here on Avvo for an attorney in your area who has experience with the OAG. Good luck.
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