In mid to late November 1967, Paul McCartney was approached to write a theme song for a new television show featuring Cilla Black as host. As both Mr. McCartney and Ms. Black were clients of manager Brian Epstein, I'm sure this arrangement had been previously handled by him before his passing. The confirmation for the theme song would have probably been an afterthought, or maybe Mr. McCartney was too busy with the "Magical Mystery Tour" project.
Whatever the case, a demo was constructed of the song in late November of 1967 and features Paul singing and playing acoustic guitar. There are three verses, although no lyrics for the second verse are sung but simply hummed as the lyrics are incomplete at this point. The demo is probably a run-through of the song to show DJ Kenny Everett how is goes as he was the one who recorded it in horrible quality and is featured on a vinyl bootleg entitled "Abbey Road Revisited".
On November 21, Paul McCartney met up with both Cilla Black and George Martin at Chappell Studios in London to record a proper demo of the song for orchestration and arrangement purposes. The run through of the song features Cilla on vocals and Paul on acoustic guitar with both of them humming through the instrumental break in the middle of the song. This time, all verses are complete. The demo/rehearsal was also filmed (probably by Tony Bramwell) for future use. This demo was officially released on the CD box set: "Cilla 1963-1973 The Abbey Road Decade". I've included a nice copy of the Cilla/ Paul demo...beautiful song !!