As long as these issues are not covered in a union or employment contract, or the changes are not made because of discrimination, the employer can make any or all of these changes, and the employee has no recourse. The changes cannot be due to discrimination or to punish a certain class of workers.
In today’s tight economy it is common to require employees to pick up the tasks that were previously assigned to employees who have since been laid off. For economic reasons the employer may also change the hours of work or eliminate an entire shift. Due to rental costs or economic consolidations, employers may relocate entire workplaces of certain departments. Each one of these actions, if not done to discriminate against a protected class of employees, is legal, even if it means that some employees are out of work.