Yoko in London in '77

According to the Alamy stock photo site, this photo of Yoko was taken on May 9, 1977 at London's Heathrow airport.      I find this interesting because we know that John never returned to England after he left in 1972.  

When  I look up this date in Lennonology I see that on May 6th John and Sean travel from New York to Hong Kong where John met up with David Bowie who along with Iggy Pop had just finished a tour of that country.    By May 11th Yoko had caught up with her family in Tokyo.   So I would say that this photo was taken while Yoko was en route to Japan.   She maybe had a layover at the airport and did not leave the airport.    However, I do find it interesting that she was in England during the late 1970's while John never returned.