Studio One, Aeolian Hall, London
An interview with Brian Matthew, taped between 2:15 and 2:45 pm at the BBC's Aeolian Hall premises in central London for inclusion, in three parts, in the Christmas Day edition of Saturday Club, broadcast in the Light Programme between 10:00 and 11:30 am.
As well as indulging in typically humorous badinage with Matthew, the Beatles also decided to ham-up a quick, vocalized version of the program's instrumental signature tune "Saturday Jump", usually performed by either Ted Heath and his Orchestra or Tony Osbourne and his Jazz Group Listeners on Christmas morning duly heard 15 seconds of the Beatle's scat rendition segued into Heath's disc version at the start of the show.
Source: The Complete Beatles Chronicle - Mark Lewisohn