I recently ordered a bag of this flavour booster for the first time in about a year, and it tastes very different to what I remember! It’s just like chocolate with not a lot of mint. I remember with the old one, the minty smell would hit me as soon as I opened it, and you didn’t need to add much at all to the vanilla powder to get a really good mint choc flavour.
Maybe it’s just blind nostalgia 
Was the old one you ordered a 150g pouch? If so it was the old version. They all changed over a year ago, for the worse in my opinion. Old banana, toffee and caramel forever in my heart. 
It used to be all mint and no chocolate… but a more chocolatey version sounds like something I would like to try again
We launched our new Flavour Boosts towards the end of 2019 to be a smaller 100g sachet. Nothing has been changed in production since then. 