The current members of Yes are:

Steve Howe 🎸🎤
Geoff Downes 🎹
Jon Davison 🎤
Jay Schellen 🥁
Billy Sherwood Bass 🎸🎤

"Roundabout" is from their '71 album "Fragile".
It was the first song of the encore and their second to last Song of the show.