Type1,
The question you ask is one which has been discussed many many times - and the answer is that there is no definite answer.
The full list of how to log time is in LASORS (off the top of my head, I think it's section A appendix B, but I might be wrong). This lists just about every conceivable way of logging flight - except for that of a qualified PPL having a checkout with an instructor.
There are 3 schools of thought on this one:
1) PPL logs P1, instructor is a passenger. This is legal if the P1 is current for carrying passengers, but is probably not correct. If the instructor is not happy with the flight, he has no legal right to take over the controls, since he is not P1. Probably left well alone - or, if you do go down this line, agree beforehand with the instructor that he will not log the flight.
2) PPL logs PUS, instructor logs P1. There is no suggestion in any written document that this is either correct or not correct. It seems the most logical solution, but there is a reasonably good argument that it is not allowed. But then there is......
3) PPL logs PUT, instructor logs P1. This is absolutely definitely allowed, no question.
So it's a choice between 2) or 3). Personally, I'd go for 3) every time - the reason being because there is a question mark over option 2). If you use option 2), and subsequently have an accident, the insurance company might well decide to go over your logbook, and if their opinion is that PUS is incorrect for this scenario, they may decide to not pay up because you have declared an incorrect number of hours. Whereas if you log PUT, no one will question it.
FFF
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