There were only about ten months between Paul recording his sweet and safe ‘Yesterday’…
… and John recording his strange and unsettling ‘Tomorrow Never Knows’.
That cartoon offers at least a suggestion of what came later from the same producer, Al Brodax, with the fabtabulous animated feature Yellow Submarine.
Hey! Bullwinkle shows up in TNK in funky psychedelic gear. Also interesting, Brodax and crew depicted flying bats for the weird sound Paul later admitted were created my messing with sea gull calls. SORT of on the right “track.’