Funny thing though - Corbyn still has a negative personal approval rating.

Also, looks like those who voted Labour and gave Corbyn his big swing were substantially composed of last-minuters. At present we don't know if that's Corbyn having an impact or May turning people off - she turned me off.

So, with a new leader the Tories might chip away at Corbyn's swing substantially. They'd likely only need to achieve a percentage point swing the other way to secure a majority.