Around 1972 Steve lived in Notting Hill Gate with his then girlfriend Heather Boyce, but their relationship was destined to come to an end as Steve had a determination to never get married. Ted Turner also shared the flat with Steve and Heather at this time.
Upton, at some stages of the band's career, took care of the day-to-day running of the band, earning himself the title 'The Colonel'. By the late 1980s Upton effectively had assumed the role of band manager. In 1990, Upton departed from the band owing to personal problems and a desire for a quiet life. He went on to manage Miles Copeland III's chateau in the south of France, but no longer has any active involvement with the music industry. Miles Copeland was the original manager of Wishbone Ash.
He attended the Garden Party at Liscombe Park, Bedfordshire on 31 August 2012 and briefly appeared on stage to join bandmates Martin Turner, Ted Turner and Laurie Wisefield, to the delight of the invited audience of fans, music press, friends and family.