I've just received my renewed UK CAA issued JAR-FCL ATPL, and as a remark in section XIII it just says "language proficiency: English". I assume they mean 'level 6', but there is no other indication. Seems somewhat vague to me
The French DGAC have decided to award all their licence-holders level 6 French (without any compulsory test or exam), so it would seem reasonable that all CAA licence holders should be awarded level 6 English.