Rearranging the letters of 'O, the Beatles retire' gives:
To rehearse 'Let It Be.'
(by Adie Pena by hand) (2007) (pending approval)
Other related anagrams without their own page:
"Sir Paul McCartney, singer of The Beatles and Wings" -> "Geriatric windbag, useless remnant. (Plenty of cash.)" (by David Bourke using Anagram Genius) (2004)
"The late John Lennon, Sir Paul McCartney, the late George Harrison, and Ringo Starr" -> "In long careers, they all once sang major hits in a rather talented Northern group." (by Larry Brash) (2004)
"Dick Rowe to Brian Epstein: "Groups with guitars are on their way out."" -> "George Harrison, surprised: "A bit patient with you, we can work it out."" (by Adie Pena by hand) (2008) (pending approval)
"The Beatles' long-playing record "Sgt. Pepper's Lonely Hearts Club Band"" -> "Highly regrettable concern: Pop legend Paul plays bass better on LSD." (by Adie Pena by hand) (2008) (pending approval)
"The former Beatles singer/bassist Paul McCartney" -> "Being that silly scouser, a perfect embarrassment!" (by David Bourke using Anagram Genius) (2004)
"Beatles" -> "Be stale." (by Joe Fathallah by hand) (2004)