I got more information, from Bob Kisin, a member of the Buttonville Flying club:
"I was there yesterday & spoke to a club member. Loch Sloy is a British Company that owns the property. This has long been the case, apparently and the PEFC rents their clubhouse & a hangar from the owners.
The PPR isn't enforced as far as I know (at least on fly-in days). However, because the runways are not maintained in winter, a call regarding current conditions is suggested. Many PEFC planes "live" at other airports in the region."
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