The danger area name is Cabillaud Radar, they are potentially trigger happy and not always there.
Several times heard traffic call Jersey as Cabillaud does not respond, after a telephone call they either say yes or no but don't enter until they say OK.
The best bet for the West of France is fly via Jersey, refuel VAT free, and maybe stay a night, £3 per 1/2 ton & 7 days free parking. The French think of the Channel Islands as local so are more receptive with landing fees & customs.
Happy landings.
FB