That happens to all new teams joining a league at all levels their acceptance has to be voted on by the members and then elected. In the old days it happened every year with clubs at the bottom of the then div 4 seeking re election. some where re-elected some werent. This applies to QPR.
I would think that whether or not they were technically legal in the eyes of the courts is irrelevant as the club s voted for the rules so they become the rules for the FL to enforce by the choice of the participating members.
Wouldnt the courts adopt the attitude that they did when Steve Foster took the FA to court, they said that clubs accept the rules on entry so the court can not get involved.