Child custody, visitation and all support Orders made at an Order To Show Cause Hearing based upon an agreement of the parties can be modified at any time. Child custody, visitation and all support Orders and made at trial can always be modified whenever there is a significant change in circumstances. Spousal support Orders can always be modified unless your Order states that spousal support is non-modifiable. Allocation of property and debt at trial is generally non-modifiable, unless the Judgment can be set aside for a particular reason. The grounds for setting aside a family law judgment are found in the relevant Family Code Sections, which states as follows:

Family Code § 2121. Provides the authority of court to provide relief, and states as follows:
"(a) In proceedings for dissolution of marriage, for nullity of marriage, or for legal separation of the parties, the court may, on any terms that may be just, relieve a spouse from a judgment, or any part or parts thereof, adjudicating support or division of property, after the six-month time limit of Section 473 of the Code of Civil Procedure has run, based on the grounds, and within the time limits, provided in this chapter."
"(b) In all proceedings under this chapter, before granting relief, the court shall find that the facts alleged as the grounds for relief materially affected the original outcome and that the moving party would materially benefit from the granting of the relief."
Family Code § 2122. Sets forth the grounds for relief; limitation of actions. It states as follows:

"The grounds and time limits for a motion to set aside a judgment, or any part or parts thereof, are governed by this section and shall be one of the following:"

"(a) Actual fraud where the defrauded party was kept in ignorance or in some other manner was fraudulently prevented from fully participating in the proceeding. An action or motion based on fraud shall be brought within one year after the date on which the complaining party either did discover, or should have discovered, the fraud."
"(b) Perjury. An action or motion based on perjury in the preliminary or final declaration of disclosure, the waiver of the final declaration of disclosure, or in the current income and expense statement shall be brought within one year after the date on which the complaining party either did discover, or should have discovered, the perjury."
"(c) Duress. An action or motion based upon duress shall be brought within two years after the date of entry of judgment."
"(d) Mental incapacity. An action or motion based on mental incapacity shall be brought within two years after the date of entry of judgment."
"(e) As to stipulated or uncontested judgments or that part of a judgment stipulated to by the parties, mistake, either mutual or unilateral, whether mistake of law or mistake of fact. An action or motion based on mistake shall be brought within one year after the date of entry of judgment."
"(f) Failure to comply with the disclosure requirements of Chapter 9 (commencing with Section 2100). An action or motion based on failure to comply with the disclosure requirements shall be brought within one year after the date on which the complaining party either discovered, or should have discovered, the failure to comply."
Family Code § 2125. Actions or motions to set aside judgment, states as follows:
"When ruling on an action or motion to set aside a judgment, the court shall set aside only those provisions materially affected by the circumstances leading to the court's decision to grant relief. However, the court has discretion to set aside the entire judgment, if necessary, for equitable considerations."