vintage ATCO,
Why don't you speak to them and see if they'll get their AIP entry change
That's not that easy. Like I already mentioned, there are different "categories" of airfield certification.
If it's a "public" airfield, then you will usually not find the PPR, except for particular types of aircraft. One airfield I know used to have PPR for powered gliders because there wasn't always parking available for their long wing span.
Then there are the "special" airfields, which are completely restricted in some way and are not REQUIRED to be open at all times. These, at least in Germany but I'm sure elsewhere, are ALWAYS PPR (check various fields in your AIP and I think you'll noctice this as true... though there may be exceptions)! And it means what it says, either call ahead by phone, or just fly there and try by radio but with the possibility of being refused, so plan accordingly.
Westy