I don't have any docs to hand to quote, but.....
I'm pretty certain that, when flying instructors have made attempts to get exemptions from Rule 5 for training flights carrying out PFLs, the CAA's response is that no exemption is necessary because it's possible to carry out a PFL to a level well below 500' already so long as you remain clear of people, structures, etc etc....
I'm sure someone will correct me if I've got that wrong.
FFF
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