Cast your collective minds back folks. June 14th 2016, these words were uttered in the House of Lords:
As far as the Treasury is concerned, it does not impose duty on e-cigarettes because tobacco is not involved and it has no plans to do so.
A sentiment that has been echoed elsewhere (though, irritatingly I can’t find the link) by a Health Minister/Secretary/Under-Secretary.
Long story short, the UK Government has “no plans” to introduce taxation of vaping products.