On March 05 1963, The Beatles had completed two tracks for the upcoming single, "From Me to You" and "Thank You Girl". Another song was attempted in the evening session. This was an early Lennon/McCartney song entitled "The One After 909".
There were five takes of the song and the feel and tempo of the song are entirely different than the later version that appeared on "Let It Be" when it was recorded on the rooftop of the Apple building (3 Savile Row, London) on January 30 1969.
This 1963 version is slower and has more of a Rock and Roll feel similar to the previously recorded "Thank You Girl".
Most of the takes are incomplete and the track breaks down. The song was never used and was never released in this arrangement during the Beatles' active career.
"The One After 909" (1963) only saw the light of day during the 1980's on bootlegs such as "Sessions" and a lot of Beatles fans were not even aware of it until then.
It was finally released on the Apple LP/CD "Anthology 1" and this version is a combination of takes 4 and 5. I don't know the purpose of the song as it could have maybe been used as an alternate "B" side and/or an upcoming EP or LP track.