The actual text of the Constitution is the final and absolute yardstick all laws are measured against. When the Supreme Court considers the constitutionality of any law it must measure the law against the original text of the constitution and its plain meaning when it was written.
Notice of working hours/changes. Your employer must give you reasonable notice of any changes to your working hours, such as cancelling your shifts. They may request last minute changes (such as ringing you that morning to say that they do not require you to work) and you can choose to agree to this change.
Labor Standards -- Work breaks (rest periods). The state law requires employers to provide restroom time and sufficient time to eat a meal. If the break is less than 20 minutes in duration, it must be counted as hours worked. Time to use the nearest restroom must be provided within each four consecutive hours of work. Meal time applies to employees who work eight or more consecutive hours.