I've been to three different Walmarts in my area this week and only one of them carries Ultra, and they've only got 5w20 (I bought their last jug of 5w30 a couple of weeks ago)
Right now I have two 5L jugs of Ultra, and so I need one more jug in order to have two oil changes worth for my Vette. So I figure I had better search now for that last jug, just to be sure I've got enough Ultra for two oil changes. Then after that, if they discontinue it, I'll figure out a new oil to run in the end of 2013 (since I will only need to do one oil change per year now that the Vette is not my daily driver)