P1/S or PICUS as its now known in JAR can only be logged on completion of a passed flight test with an examiner.
It can't be logged at any time with a FI onboard unless you are on an Integrated commercial course.
Club check outs and a whole raft of other "check outs" have to be logged as Dual or if the instructor is willing and doesn't log anything as PIC. Whoever signs the tech log as PIC logs the hours as PIC.