I have no idea. The CAA has not given me a reason (yet) why the certificate is not acceptable to them. The certificates issued by this institute were certainly acceptable to the Dutch authorities, since a few hundred pilots from my local flying club all went to this particular language institute.
(The language institute designated examiner was a highly esteemed and kind fellow flying club member, and the exams were held at the club, so that made things very convenient. In fact, there was a bit of a mix-up with the scheduling of my exam and when I accidentally bumped into him at the club at another time, he said “want to do the exam right now?” Twenty minutes later I had my LPE 6 – and was 130 euros poorer.)
