Sort seasons by date no longer works properly

It used to work., By clicking on dates, it used to sort seasons by ascending or descending date. Now the sort seem to work alphabetically resulting in season being sorted out of order date-wise. 

In what way is this not working?  The recurring seasons don't sort that way, of course, because they don't have a proper beginning or end.  But if you disregard those, the rest do appear to be in descending order, as they should be.