According to graffiti in Pittsburgh’s Oakland neighborhood, this Friday is “92.1 WPTS Day.”

WPTS-FM (92.1), the 16-watt Class D radio station operated by students at the University of Pittsburgh, is celebrating the holiday with a series of free rock concerts starting at 2 p.m. on Forbes Quadrangle. A Squirrel Hill store is providing free cupcakes. (Cupcakes and loud rock music? Two of my favorites!)

In case you’re still stumped, Friday is “9/21” … as in “92.1.” There’s still more than a week to plan for WLTJ Day (9/29), but WTZN Day will have to wait until a few more days are added to the September calendar.