Rangers' Chairman Green says that his team will be in English leagues within 5 years...they will play their way through the lower leagues. Any attempt to block them will be restraint of trade under European Law (he says). Don't know the fine detail of that, but we have the precedent of Swansea and Cardiff (though their inclusion was because they were already in the league when the Wales league was formed).
That old chestnut..! The last time Rangers [and Celtic] tried to get into the English League, around 12 years ago, the FL welcomed them with open arms, and the PL vetoed it. So much for competition.