I would not be sure about the original premise of "increasingly higher numbers of Plat" - do we have any supporting data?
To the main question - it doesn't seem to be restricted to family. (OTOH it's quite an interesting thing what a commercial entity may or may not deem to be "family" these days without being charged with discrimination? Subject for another discussion)
Having said that, should one would put an announcement on huuto.net or similar, I wouldn't be surprised if AY would at least investigate.