To revalidate a rating you must:
- within the 3 months before the rating's expiry date, pass a proficiency check in the relevant class in accordance with Appendix 9 to this Part with an examiner;
or
- within the 12 months before the expiry date of the rating, complete 12 hours of flight time in the relevant class, including:
- 6 hours as PIC;
- 12 take-offs and 12 landings; and
- a training flight of at least 1 hour with a flight instructor (FI) or a class rating instructor (CRI).
You are exempt from this flight if you have passed a class or type rating proficiency check or skill test in any other class or type of aeroplane within the 12 months before the expiry date.
Above from here:
Revalidate a SEP Aeroplane Class Rating | Private Pilots | Personal Licences and Training
I cannot see how the student can log as P1 the "training flight of at least 1 hour with a flight instructor (FI) or a class rating instructor (CRI)". If it's a training flight, surely it must be logged as dual.