The 4831 I am loading is SURPLUS 4831.
They sold it in the 60s and I have been using a little each year.
Still performs well!
Your experience may be different.

Hell, two years old ain't nothin'. I know some small time FFL dealers who have some unopened 1 pound cans on their shelves, going unsold for more than 10 years and I'd bet the farm it's still as good as the day it was manufactured.

Personally, I still use some Bullseye I bought in 1971. It fires 38 specials just as well as way back when. Once upon a time I bought some Dupont IMR powder--I think it was 3031 if my memory of the color of the can is correct. Screwed off the cap, peeled off the seal and a reddish dust arose from the spout. Every grain was that color too. It smelled like no gunpowder I ever smelled before. Took it back to the store with my recent receipt and got my money returned. Now I have firsthand experience if any of my stockpile ever looks and smells similar. It will be spread on the front lawn as fertilizer. I won't even try to light it off in one of my firearms. No use taking any chances.