I don't have one on mine. I bought mine through the computer too. Mine has a small letter B or a number 6 down there, but otherwise no discernable notch. Smell the juice and see if it smells normal. I can't really see distribution of seconds of the juice inside, and think that unlikely to the point of disbelieving it could be true.
Live in it for a day and see if it's right. Word on Scentiments is always good too.