Maybe they meant to say 0.4, without any qualifier - i.e. that the rate went from 0.7-0.8 to 1.1-1.2? A change from the lower end of the old range to the higher

Maybe they meant to say 0.4, without any qualifier - i.e. that the rate went from 0.7-0.8 to 1.1-1.2? A change from the lower end of the old range to the higher end of the new range would match the 70% increase in transmissibility. (though that would require an increase of almost 0.5)