Only one pilot can log PIC in a single pilot aircraft under JAA regulations.
So if the instructor is logging it at all - then you will be logging the flight as dual.
If you are logging it as PIC the instructor can't log it all.
At all the clubs/schools I've attended, the checkout is logged as dual as instruction is normally provided even if only a small amount, and the instructor is normally paid. The checkout is also normally also provided for insurance purposes and a qualified instructor must provide that checkout. Therefore the instructor is providing a service and instructing, and therefore they log it as P1 or dual given, you should log it as dual.
I've heard of some people being told to log it otherwise but I can't see at all how it would comply legally.