Question about this 1933 World Wide Gum Ace Bailey Hockey Ice Kings card

rbdjr1

Notice below how this card seems to be spotting. My question is, "does this spotting process continue after the card is slabbed? Or will proper storage, out of the light, curb this spotting process?

BTW, key card!

rd

Ace Bailey Link

scooter729

I own this card in a PSA 4 and had mine slabbed about 4 years ago, and it hasn't had any worsening effects like this. I imagine what you're seeing on the card was there pre-slab.

EagleEyeKid

That's a very generous 7.