It sounds like the kind of at-will employment that most US employers use. Most US hourly jobs--retail, food service, etc are like this but I've had office jobs where the employer would often tell us to come in more or less depending on the need. And of course, you're still expected to give notice to these jobs and they don't provide vacation or other time off. So it's moving towards the US system, which is probably not a good thing for employees.