Welcome to a new feature of CLEL: "Free Advice Wednesday." I'll be posting on topics that come up from time to time that I think are worth getting out there. Of course, as a disclaimer, you should never do what I say, this is all hypothetical, etc.
There's no maximum time a salaried* employee can work, right?
Employees can work 24 hour days, but they can't work for more than six days per week, on average. There are exceptions for emergencies, protection of the loss of life or property, CBAs, and a few other rare circumstances. The DLSE can issue exemptions, though, if they choose to any employee or employer.
It's a misdemeanor if you don't comply and it also has typical Labor Code penalties associated with it too.
References: Cal. Lab. Code §§ 550 et seq.
* This is the term that is going to most likely be used in a question asked to me. For the purposes of this question, I'm going to assume that in addition to they're being non-hourly employees they are also "exempt" employees.