Why do "Part Time Teachers" work 60-hour weeks?

A little background on all the changes at Japanese Schools (come April)
As you know, the new school year starts at the beginning of April in Japan. And with it comes a lot of changes, not only for the students, but also for the staff.

Within a contracting organization (for us, it's the Hyogo Prefecture Board of Education, or BOE), teachers can be moved from school to school at the BOEs discression. These changes can be really big (my friend has 22 new teachers at her school this week!) and some are minimal (we have 3 new ones and a new vice principal). It's not the norm, but some people have also been moved hours away from their previous place of employment in the past, meaning that they have had to move (and sometimes teachers even live a distance from their family for a year because of unexpected assignments). Full -time/"real" teachers have more say and can sometimes stay at one place for 10-15 years, but it is common for people to be moved every three years (once you have experienced the full student cycle)... and - seriously - they really can move you anywhere. This is a way to get to know the system well, but it also poses a lot of CHANGE.

Wait, what is a "real teacher"... are there people who aren't "real" teachers?
In order to be a "real teacher" in Japan, you need to finish university (not necessarily study pedagogy) and then pass a licensure test. Japan differs from America, where you need to study being a teacher, pass the test and do student teaching before you can even enter the classroom. Many Japanese teachers (in all subjects) work for years before passing this test and many fail the test multiple times. There is actually a set number of people who can pass the test each year, so it doesn't matter if everyone rocks the interview section (then followed by a written section on teaching and another on your subject matter), chances is you're going to have to take it more than once.

When you pass the test, you're a "real teacher."

The thing that baffled me when I first arrived was that the teachers who haven't passed this test do the same thing as the other teachers, sometimes have more expertise in the subject or in the classroom, but are considered lower (esp on the pay scale) and called "part-time teachers." But they work 60 hours a week. Most teachers in Japan spend long hours working (leaving at 10 or 12 during testing periods) and have to go to student's homes and stuff... these so-called part-timers are no exception. Considering many of them have a bit more experience than new "real" teachers, they really only differ in the fact that they don't get tenured and thus work on a year to year contract.

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Anyways, I know this information is a little random, but it's not second nature and thought it was worth sharing. I fit somewhere in the grey zone of this whole teacher categorization at work (or rather, I'm not really in this scheme at all) and I've found it really interesting to learn more about as an observer. I just feel bad for my friends that are "part time" and have been teaching for 8 years... I guess just because the system is really different doesn't mean it's wrong, though.