My local 7-eleven has started carrying new double gulp cups. I didn’t seem to notice anything strange when I got one until I sent it down next to the old cups I keep around for refills. After doing a little experiment (Filling the old with water, pouring into the new one until it was full) I realized these are no where close to the same size. nIn short if you have the old cups keep them around, that way you don’t get ripped off.
50 NW Main Street Winston, Oregon United States of America