It's no longer labeled vegan. A lot of producers actively avoid the label, despite the fact that the Vegan Society would provide their stamp of approval. I've heard somewhere putting it on your product lowers sales. All this to say, are you certain it's actually not vegan anymore?
It looks like the 91% natural ingredients version has benzyl alcohol as a preservative which is typically synthetically derived and in my experience can drastically shift the bio-based ratio.
As far as I can see, the rest of the ingredients are the same, but the sourcing of those ingredients could be different which could also shift the naturally derived percentage.
I wouldn't even be surprised if this is just a shift in marketing. The "Vegan" label, in particular, has fallen out of style as more and more men become obsessed with meat-based diets.
I think you might have gotten old stock when you bought a 'new' tin. When I look on their website, it only has the vegan formulation listed, and the ingredients do appear to be derived from non-animal sources.