There is no time limit for setting petitions for hearing, though, generally, you can move to dismiss them if no activity occurs on the case for a full calendar year. In fact, the clerk will often ask that petitions be dismissed after a year of inactivity. But there is no rule that says only a party can set their own motions. You can set a hear on the supplemental petition, too. Other things may need to happen before the hearing, though. For instance, both sides may need to complete mandatory disclosure, discovery or mediation. By the way, your ex has no legal right to reduce payments without a court order, even if he has filed a supplemental petition. You may want to consider a motion for contempt.
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