The physical building is in Thornbury.
I'm not up with it but it used to that you used it if you were too remote from a school, that you were living overseas, that you were ill or incapacitated in such a way that you couldn't get to school or for single subjects that were not offered at your school.
I did one subject when I was a kid, one kid of mine did one subject and I have 'supervised' kids who did single subjects by distance ed while attending normal school.
All in the past but it is well established and gets good results. You didn't used to be able to use it just because you liked the idea, you needed a reason. It seemed like the volume of work was morethan usual and there was pressure to get your work done and in regularly. Good for disciplined kids who like structure. Kids always liked going in and meeting their teacher and other kids.