That’s interesting. This is slightly different than another article I have from smoking pipes. Where it says hour (in green) it says day in my article. This must be updated, the one I reference is a lot older so maybe this one is correct.
I’ll try to find the link to the one I’ve always used.
And here's a more recent tin of DSK I purchased myself from a retailer and wrote the purchase date down. Doesn't mean that was the date it was manufactured but the year correlates.