This is a technical giving the judge discretion. Code of Civil Procedure § 430.40 states:
- (a) A person against whom a complaint or cross-complaint has been filed may, within 30 days after service of the complaint or cross-complaint, demur to the complaint or cross-complaint.
- (b) A party who has filed a complaint or cross-complaint may, within 10 days after service of the answer to his pleading, demur to the answer.
Extensions to respond to the complaint AFTER the initial 30 day period do NOT keep open the time to demurrer! Crazy? As with many things, the trial court has discretion to consider an untimely demurrer if it does not affect substantive rights of the plaintiff. (Jackson v. Doe (2011) 192 Cal. App. 4th 742, 749–750). The 30 day language is not mandatory and only applies to the initial demurrer not to amended complaints. (McAllister v. County of Monterey (2007) 147 Cal. App. 4th 253, 280)
The court can also increase the time to file a demurrer “in furtherance of justice”. See also CCP §473(a)(1).