Arizona courts award spousal maintenance and child support based upon circumstances at the time the court makes the order. Often, the parents' or former spouses' circumstances change. Incomes change, day care costs change, insurance costs change. Many people think that they can go to court in a few months and modify child support or spousal maintenance effective as of the date the circumstances changed. However, Arizona courts have repeatedly held that they cannot modify child support or spousal maintenance retroactively to a date before the date that the person seeking a modification filed the petition to modify. For example, Father pays $500 per month pursuant to a child support order. In January, he loses his job, but quickly finds another…