To make things more clear cut, I predict that Britain will not leave the EU within 5 years, but really I don't think they will leave ever. There will be a day when people stop calling it England or Britain that will occur before then. It will cease to be what could be recognized as a nation-state by today's standards before that happens.
I'm not saying that those other things will happen eminently. I'm saying in terms of timeline, England is no longer England, England leaves the EU (it can't because it doesn't exist), the heat death of the universe.
But to make it more measurable. 5 years, it won't happen.