Matrix : Ordering column when NO rows

I don't think you've done anything wrong here, I think you may have found an issue in the matrix visual in that once you have assigned a sort order based on one of the measures there is no way to turn off that measure based sorting. One work around that worked for me was to remove the measure that was being sorted and then re-add it.

So in your case if you remove the [Search Result Views] measure from the matrix you should see the months go back to their alpha-numeric order, then you can add the [Search Result Views] measure back.