Legal Question in Administrative Law in California

I can't comment, obviously, on anything that might be in a collective bargaining agreement,

Labor Code section 510(a) is the applicable state law. It says:

"Eight hours of labor constitutes a day's work. Any work in excess of eight hours in one workday and any work in excess of 40 hours in any one workweek and the first eight hours worked on the seventh day of work in any one workweek shall be compensated at the rate of no less than one and one-half times the regular rate of pay for an employee. Any work in excess of 12 hours in one day shall be compensated at the rate of no less than twice the regular rate of pay for an employee. In addition, any work in excess of eight hours on any seventh day of a workweek shall be compensated at the rate of no less than twice the regular rate of pay for an employee.........."

"Workweek" is defined in Labor Code section 500(b) as ".....any seven consecutive days, starting with the same calendar day each week. "Workweek" is a fixed and regularly recurring period of 168 hours, seven consecutive 24-hour periods."

Based on the foregoing, I'd say regular pay. You worked 40 hours within 168.