I thought I was going blind (er) but looked all over my last Wyeast Ale liquid pack yesterday and could find no date of manufacture . Seems they are only printing “Best if used by xxxx “. Dates on the package. Prob doesn’t make a ton of difference but it was fun to see the estimated cell counts and calculated effects of starter/ stir plate.
Maybe too many packs were being left behind at the home brew stores as people of course grabbed the freshest.