Preschool will likely be covered by section 23.
With respect to post-secondary education, it's somewhat debatable. As I mentioned, you can't assume that all post-secondary education programs or institutions will be covered by section 23. When you look at the history of section 23 case law, it's clear that this was not necessarily the intention of its authors. As I said, the concept can be applied to faculties of education or certain faculties whose services are required to ensure the quality of education. I don't think we can yet claim that the courts will accept that all homogeneous post-secondary institutions be covered by section 23.