Reanalysis of cheese as an adjective

My brother-in-law (sort of - my partner's brother) sent me a text recently that included the name of a type of a squeezy cheese that comes in a tube, called Primula. It looks like this (this is one that - bizarrely - has prawns in it):

He was texting to tell me that his cat likes it, if you're interested. There's no accounting for taste, I suppose.

Anyway, point is, he spelt it Primular. (He has a non-rhotic accent, being from North-East England so it sounds the same as the actual brand name.)

So is this spelling error due to the reanalysis of the name Primula as an adjective, primular? Would it be a type of cheese, primular cheese? I wonder what it means. It sounds a bit like rectangular, regular, circular; I wonder if it's to do with the shape?

Perhaps it's more linked to primary, and it is the supreme squeezy cheese, the squeezy cheese above all other squeezy cheeses. I wouldn't know, as there is no way in the world I'm going to eat that.