TODD contest (conservative): 120 days from date of beneficiary's 5681 notice to heirs

(b) The notice required by subdivision (a) shall be in substantially the following form: ... If you believe that the revocable transfer on death deed is invalid and you wish to stop it from taking effect, you have only 120 days from the date of this notice to file a fully effective challenge. You should act promptly and may wish to consult an attorney.

CCP 12: "The time in which any act provided by law is to be done is computed by excluding the first day, and including the last, unless the last day is a holiday, and then it is also excluded." CCP 12a(a): "If the last day for the performance of any act provided or required by law to be performed within a specified period of time is a holiday, then that period is hereby extended to and including the next day that is not a holiday. For purposes of this section, “holiday” means all day on Saturdays, all holidays specified in Section 135 and, to the extent provided in Section 12b, all days that by terms of Section 12b are required to be considered as holidays." CCP 12b: "If any city, county, state, or public office, other than a branch office, is closed for the whole of any day, insofar as the business of that office is concerned, that day shall be considered as a holiday for the purposes of computing time under Sections 12 and 12a." CCP 10: "Holidays within the meaning of this code are every Sunday and any other days that are specified or provided for as judicial holidays in Section 135." CCP 17(b)(4): "“Month” means a calendar month, unless otherwise expressed." Prob. Code 1000(a): "Except to the extent that this code provides applicable rules, the rules of practice applicable to civil actions, including discovery proceedings and proceedings under Title 3a (commencing with Section 391) of Part 2 of the Code of Civil Procedure, apply to, and constitute the rules of practice in, proceedings under this code."