Undeterred, and with fundraising support from the Toronto musical community, the group purchased new instruments and pressed on to record the album. "Long Lost Relatives" was issued in 1971 on Finkelstein’s True North label. The album included Mills-Cockell’s "Tillicum" and the four "Stringspace" pieces (which, owing to the space restrictions of the LP medium, spanned both sides of the LP), rounded out by three additional Mills-Cockell compositions: "Tumblers to the Vault", "Better Deaf and Dumb from the First", and "Aurora Spinray". "Tillicum" was also released as a single, and peaked at #38 on the Canadian charts in 1971. The group disbanded in 1972 as Mills-Cockell, Wells, and Pringle went on to pursue other projects. On 24 August 2016, RVNG Intl. announced the release of "Tumblers from the Vault", a remastered collection including Syrinx's entire released repertoire, together with some previously-unreleased tracks, including the audio recording of the CBC "Music to See" performance of "Stringspace". "Tumblers from the Vault" has been released on 14 October 2016. In the years following the 1972 break-up of Syrinx, Mills-Cockell released a number of solo efforts, including "Heartbeat" (True North, 1973), "A Third Testament" (True North, 1974), "Gateway" (Anubis, 1977), "and Do Your Hear the Rushing River?" (1995). He also released a cassette of "Stella in Black and White", a collaboration with poet Blake Parker, in 1994. In 2004, Mills-Cockell released on CD his seven-movement "Concerto of Deliverance", an "extended tone poem with words," with libretto by Blake Parker. Mills-Cockell has been active throughout his career in musicals, and has composed over 100 scores for plays in theatres across Canada. Many of his works not specifically created for dance have been adapted by dance troupes, including "Belong", by the Royal Winnipeg Ballet, "Ariel Ribbon", by the Anna Wyman Dance Theatre, and "Jouney Tree" and "Chant for Your Dragon King" by the National Ballet of Canada. He is currently working on bringing "Savitri and Sam", a full-length opera he composed, with libretto by Ken Gass, to the stage.