It had long been the case that you could fly French airways VFR at quadrantle levels.
Pace,
I don't want to start another fruitless argument, but that is not right in a number of ways.
Firstly the quadrantal rule does not apply in France. What you mean is VFR levels, which is the appropriate IFR level plus 500'. If you flew NE at at Odd level, as you would under quadrantal, you would be in big trouble.
But much, much more important is that you do
not fly the airways at VFR levels. Airways do not exist at VFR levels. You are flying the route of airways in Class E airspace, in the hope that they will keep you out of restricted airspace.
This hope is entirely misplaced. I cannot put that strongly enough.
It is not uncommon for the French IFR controller to reroute you off an airway because of military exercises. Flying VFR you do not get that service (unless you are lucky enough for FIS to tell you, but that is not obligatory on either part.)
Furthermore, airways at low levels can pass through Class A, C or D airspace, for which you need a clearance.
Flying IFR on airways you are cosseted and protected by ATC.
Flying an airways route through Class E under VFR you are not, and, frankly, and speaking as someone who does this all the time, you are much better off flying in a straight line through Class E and D, partly because it's quicker, and partly because it makes quite clear to you your obligation to make your own arrangements to stay away from restricted airspace.
You get the same (now excellent) radar assisted FIS service as you would get on an airways route.