Thomas - I have heard that "who must retain line of site And remain outwith 150m of vehicles, vessels, persons, structures unless exempted also" is actually incorrect (and by you of all people). It is 50 metres, reducing to 30 metres during take-off and landing and if all are under the control of the operator, it would seem as close as he/she likes!. 150 metres applies to congested areas and crowds.
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