When is a referendum not a referendum? Answer — when it is a politically convenient device used by a slippery Prime Minister in trouble with half his MPs.
The EU Referendum held on the 23rd of June was phony. It has no legal consequences. That in turn means that it has no effect. Whoever becomes leader of the Tory Party and thus Prime Minister of Great Britain, will, if she or he wishes to cause the UK to leave the EU, have to follow the normal Parliamentary procedure for the making of law. It could take years for legislation to pass, if it is not blocked from the start by the majority of pro-EU MPs.