In June 2003 FCL issued FIs with Guidance Notes for 'Differences Training in Accordance with JAR-FCL 1.235 and 2.235' which includes the sticky labels. The labels 'are to be inserted into the student's log book on the "special qualification page" (if there is one...) following completion of the Differences Training'. It goes on to say: "As a last resort it may be included with the flight details on the daily pages". So there.