They will do “Lola” for the first time. That’s a promise. The Muswell Hillbillies, a Kinks tribute band, are playing what has become an annual tradition on their home turf, a single show at the Iron Horse in Northampton. And once again, Dave Simons, the 11-piece band’s organizer, says the Sunday night show may be their last. When the Hillbillies started, back in 2010, the members were a mix of adults and local high school students. Now, the kids have moved on to college, leaving seasoned pros like Simons and drummer Dave Sokol to organize the show. “Nothing’s changed except everybody’s getting older,” said Simons. “We’re down to one teenager.” The show will draw from the catalog of Kinks songs the Hillbillies have played over the years, ranging from beloved rarities (“Harry Rag”) to the group’s biggest hits, including “You Really Got Me.” Simons notes that Emily Eagan, who plays trombone and accordion, will take the microphone for the studio version of “I Go to Sleep.” Proceeds from the show are going to businesses displaced by an October fire that destroyed a strip mall in nearby Hadley.