Grey v4 - different smell or i'm going crazy

At the risk of sounding like a crazy person…

Did something change in the v4 formulation recently? I could swear the new cartridge i bought a week ago (arrived today) smells slightly different than gray v4 used to. The sticker on the bottom says 2019 10 15 as far as i can tell.

The smell is a little bit less “bitey”, and a bit closer to the smell of PVC.

Maybe i’m coming down with flu.
Or maybe i am going slightly crazy.
Would expect the version to change if there was a change in the formulation, after all…

Now it’s heated up, it smells a bit more acrid, but still different (acidic with a sweet note).