Sorry, nothing dramatic, a lot of French services (public and private) were and have been on strike the past couple of days, so it's logical to go where the eng. guys are working.
Also it could have to do with fuel dump areas, the French may not have been too happy with 40T or more fuel being dumped over populated areas (i know it evaporates b4 anyone says anything) so if dumping over the sea would mean a logical diversion to NCE