Perpetual change has been a key theme in the more than 40 years that Yes have been performing as a unit. In the latest chapter, it appears that vocalist Benoit David, himself a replacement for original lead singer Jon Anderson, has been replaced.

David has been ill, forcing Yes to cancel the final portion of their European tour in December. According to a post on the band's official Facebook page, he's still recovering and will not be able to join them for the next scheduled Yes shows in April, set to begin in New Zealand and Australia.

The Facebook message says that “to avoid disappointing their fans on the forthcoming Australian leg of their world tour, they have found a replacement singer."

"Jon Davison will join Yes as lead vocalist for the upcoming dates in New Zealand, Australia, Japan, Indonesia, and Hawaii, " the post continues. "Yes really appreciate Jon Davison joining them for this leg of the tour and are sure this arrangement will satisfy all Yes fans.”

Current Yes keyboardist Geoff Downes sent out a tweet on Monday night “extending a very warm welcome to new lead vocalist Jon Davison, joining Yes on tour this spring.”

Davison is known as the vocalist for the progressive rock band Glass Hammer and also previously played bass for the Seattle-based psychedelic rock band Sky Cries Mary.

Growing up on a steady diet of Queen, Genesis and Rush, Davison eventually discovered the music of Yes, who he called his “favorite group and greatest musical influence” in an interview conducted for the official Glass Hammer site.

Benoit had been with Yes since 2008 and made his recording debut with the band on last year's highly regarded 'Fly From Here' release.

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