You might not think that you are going to have to keep taking linux courses all your life, but you will. If this is the career that you are choosing, then you will have to keep up with what is changing in the operating system. This means that not only is the potential to take more classes on the horizon, but more tests.
You should make sure that you are keeping up-to-date on all of the changes that are made since they are numerous in each new edition. This will help you to know the latest methods and even the changing technology.