Wow. Up till my last purchase on my Highlander (Continentals replaced the Continentals that were already there) I have never bought the same brand of tire twice---for years and years, and I've ALWAYS gotten a prorate from them. And they were clear with me, I could get a prorate at 4/32. In fact, a couple of months prior, I don't know if I was rotating or getting them aired up, the guy told me that I could get new ones, and this was a month or two before they were measured at 4/32 & 3/32. If you are still interested in their business, I would contact a different branch/location and ask them how low the treads have to be, and also, if you can still get a prorate if your previous AT purchase was of a different tire brand. Maybe this is just how they do business in CA? I dunno. I sure do like the prorates, but I also like pricing out which tires are the best deal, too.