@jmooring Thank you! That works for this example.
However, I am after a solution that works for more than just one level, as I have created an auto-collapsing menu that works for infinite levels of content (within a section).
If there is no way to reflect the directory structure in the permalink (and mimic the default behaviour), adding a variable like ‘:dir’ or ‘:filepath’ might be a nice feature request? What do you think?
Thank you all for your time!