Usually, when a singer gets COVID, that singer’s upcoming shows are canceled altogether. That’s not what Blues Traveler did over the weekend when John Popper got COVID. The band are currently on tour with fellow ’90s alt-rock mainstays Spin Doctors and Gin Blossoms, and so the singers of those bands filled in for Popper at their shows in New Braunfels, Texas on Friday and Thackerville, Oklahoma on Saturday. It was interesting.