If you are wondering whether you can set-aside a child support order, you need to know some basic things:
1. Do not allege fraud or perjury at all in any moving papers (or anywhere) for that matter, because the lead case on this issue, In Re Marriage of Zimmerman 183 Cal.App.4th 900 (2010) is commonly held as standing for the proposition that any allegations of fraud or perjury start the six-month statute of limitations for Family Code 3691, which is the code section allowing child support orders to be set-aside.
2. This reading of that case can lead to absurd results: a party can lie about their income and assets, obtain support orders lower than they actually should pay, stonewall discovery requests, and then turn around and use the allegations of fraud and perjury to use the statute of limitations as a defense. You are not likely to get any sympathy from the court: they will assert the statutory scheme is designed so that you must file to preserve the statute of limitations.
3. Of course, this reading of Zimmerman can lead to absurd results. If a party files on the basis of mere hearsay allegations, they will be threatened with sanctions under Family Code 271 and especially if they don’t obtain the proof they need (which happens commonly, parties can be very effective in preventing the flow of information).
4. The bottom line is you should either stay quiet, or file upon receipt of the information. The case is a trap for even the most experience practitioners.
5. Although one would hope equitable relief would be available by way of equitable tolling, equitable estoppel, or judicial estoppel (an oversimplified definition is that a party should not be able to take advantage of their own bad faith) don’t expect a court to take the risk of making a decision in your favor. Zimmerman actually addressed the argument of Equitable Tolling and dismissed it, perhaps unfairly.
http://www.mcleodlaw.us/cases/zimmerman.pdf