Forget the idea that it will be "only up to 2019". That cannot be made to work. The ridiculously misnamed Great Repeal Bill will turn the United Kingdom into a colony of the European Union.
With the acquis communautaire as the law of the United Kingdom, several of the good things that the triumph of the Old Tory Left might have made possible, especially the renationalisation of the railways, will remain out of the question.
Deviations, if any, will not be by Act of Parliament, but by Ministerial decree. Watch out for who gets to be a Minister with such responsibilities, if at all, from now on. Look up "Finlandization", although this goes well beyond that.
And if you are old enough, then consider how you voted in 1983.