They changed the chocolate recipe a while back despite their denying it. I ate way too much of the stuff, like 5-8 family blocks a week a few years back, then stopped after the change. F&N was also my favourite, then I changed to coconut rough but they stopped offering that for sale.
The amount of cocoa butter dropped and was replaced with palm oil to keep costs down. A few years ago Cadbury realised that the price of cocoa was going to soar in the not too distant future, definitely before 2020 and we'll see a big jump in price. It's also Halal certified now.
I don't usually like white chocolate, but have a coconut and cornflakes white chocolate (yes I know how it sounds) but it tastes really good.