Kumon Japanese Correspondence Course suitable for N2 level students?

I've seen a lot of people recommend this course but it was always in posts about lower level students. Do they cater to N2 and above? There's not much information about the contents on their website apart from saying they focus on reading and worksheets. Are these worksheets just further reading materials or do they teach grammar, too?

My speaking and reading really need brushing up so I was hoping their was something like this out there. If anyone has experience with this course, please let me know what you thought of it. And if it's not suitable for N2 upwards, are there any other options.

Thanks in advance!

by trashboxbozo