I agree with Stu there, Jim. It's become clear since the referendum that brexit is going to be disastrous unless promises are broken in respect of the customs union and single market. Labour is not morally bound to continue to support brexit in my opinion, but in terms of realpolitik it has absolutely no option but to stay publicly pro-brexit. If Labour now declared for remaining, you can imagine the field day the Tories would have. There are strains. Ninety percent of Labour Party members voted remain.