In the Channel Islands a lot of the instruction for the issue of a JAR PPL is carried out within the Brest FIR and we send our students on Nav Ex's solo over France. At no time in the last 40 years has this been a problem. We just have to send a copy of the medical certificate to the CAA and they issue a dispensation for a student (who has no licence) to fly outside UK airspace.
So I suggest you dont believe all that you hear.