I didn't know it changed either, but I asked a Game Warden about having venison after the date some years back.. I told him that I hunted in Ohio, Indiana, and Pennsylvania each year and took up to 12 deer... said that it would be silly to get rid of that meat by the date... he agreed, but said that I should keep the tags for the deer handy(Ohio and Indiana has mandatory checkin and give metal tags for the carcass)... So, I took him at his word and have never worried about it since then. Never thought of all the canned venison until this post...
Themoose