I got an impression that overprotective new lithops fans tend to panic over things they can easily figure out just watching their plants. :) Some happen to seriously freak out seeing a "dehydrated" lithops. It's important to know that in most cases wrinkles are not a bad thing! And it's surely much better than the opposite - cucumber shape, bursting open, 3 leaf changes a year. In my opinion, wrinkles also bring out colors nicely.
If an adult plant is in an advanced "wrinkle" stage it will bounce back and get its normal shape within 3 or 4 days after watering. Usually you can see some progress even after a few hours!
On the picture is another helmutii I bought under description "new locality" (新産地). Don't know about that but it does have quite curious yellow-orange window edges I find very appealing. Normally I wouldn't be so radical about re-hydrating it but I needed it to be tiptop for the trip. ;) The pic shows its progress within ca. 3 days. (click to enlarge)