A Post-Decree Modification is a modification that takes place after a party has obtained the Decree of Divorce, Legal Separation, or Allocation of Parental Responsibilities. Post-Decree modifications are usually modifications to Custody (Parenting Time) agreements or Child Support. Other modifications include but are not limited to Relocation, Decision-Making, and Alimony (Maintenance).
To file a modification, you cannot have filed for a modification in the two years prior. Exceptions to this are emergencies, Relocation and Child Support modifications.