When you open the box of Dior lipstick, you can see that the production date is marked on the side, bottom or inside the lid of the box. The date of production can be expressed in the form of Arabic numerals year plus month. For example, "20 19 1 1" means that the production date is 20 19 1.

In addition, Dior lipstick uses a four-character production date label, with the first number indicating the end of the year and the second letter indicating the month. Since 2008, LVMH has started to use a new batch number for cosmetics. The number of cosmetics in twelve months is N= 1, P=2, Q=3, R=4, S=5, T=6 and U=7.

I hope the above information can help you solve the problem. Please feel free to let me know if you have any other questions.