Will the Grateful Dead's upcoming "Fare Thee Well" concerts actually be the legendary band's swan song, or are there more shows to come?

In the wake of the overwhelming demand for tickets to the five previously announced shows (three at Chicago's Soldier Field, billed as the group's last-ever shows, preceded by two near the band's Bay Area stomping grounds in Santa Clara, Calif.), Billboard is reporting that shows featuring members of the Dead and John Mayer are being planned for the fall.

"Speaking to multiple sources, Billboard has learned that a fall tour featuring John Mayer is in the works," reports Billboard. "According to insiders, the trek is due to kick off in October, with the Grammy-winning singer and guitarist having already begun to jam in a rehearsal-like setting with select members of the group, chief among them [Bob] Weir. Observers say he's ecstatic about the prospect. A rep for the band tells Billboard that it's "premature" to suggest any such outing is being planned." 

Mayer, while serving as a guest host on CBS's "The Late Late Show" in February, welcomed Weir as a guest, interviewing the founding Grateful Dead member and joining him for two songs.

The lineup for the Fare The Well shows will be made up of Dead core members Weir (guitar, vocals), Phil Lesh (bass, vocals), Bill Kreutzmann (drums) and Mickey Hart (drums, percussion) as well as guests Trey Anastasio (guitar, vocals), Bruce Hornsby (piano, vocals) and Jeff Chimenti (keyboards). 

The band played what turned out to be its last show as the Grateful Dead on July 9, 1995 at Soldier Field; founding guitarist and vocalist, the iconic Jerry Garcia, died exactly one month later.