Hi Skydriller
You need to produce logbook evidence to an authorised examiner of having the 12 hours, including 6 hours PIC and at least 12 take-offs and landings. This experience must include a flight of at least one hour with an instructor (authorised in accordance with JAR-FCL to instruct for the JAR-FCL TMG or SEP rating as appropriate) for which the appropriate logbook entry has been countersigned by the flight instructor.
So, you can do your instructional flight at any time during the last 12 months of validity and the instructor must be JAA certified.
Cheers
Keith
[This message has been edited by Cahlibahn (edited 28 June 2001).]