The parties are free, however, to agree to different terms triggering a change in the obligations of the payor spouse, including the application of a standard other than substantial unanticipated and unreasonable change in circumstances as the basis for determining a modification application, provided that, in the case of child support, the children's personal right to receive adequate support is not adversely affected and public policy is not offended based on Heller v Heller,… [read post]