The badge on the door will have the production date. That discoloration below the door opening on the body is normal and just from cooking. A little Dawn and water should clean that right up. I did for me on my YS640 anyway.
Yoder Smokers YS1500, Kamado Joe BigJoe & Joe Jr., Weber: 18.5" OT(L), SJG(AU) & (DI) - Past Cookers: Yoder Smokers YS640 Comp Cart, Kamado Joe Classic, OKJoe's Longhorn, UDS, Weber: Performer(AA), Genesis Gold C(DH), 22.5" OTG(DI), 22.5" OT(L)
IMBAS Certified MOINK Baller