By 1966 the first rumors of dissension within the group leaks out. 'Berry Gordy Jr.', had made the decision that would become a solo artist and The Supremes just a showcase for her talents, sort of a launching pad. This turn of events was not received well by Mary and "Flo" as their own talents became relegated to background singers for a super star. It should be remembered that The Supremes owed their sound in recordings to Diana Ross and the lady deserved the extra credit for being an exceptional talent, but on TV or in concerts, audiences were fascinated by all three Supremes, by their performances and by their individual personalities. Gordy knew the dangers of this situation so he pursued the strategy of minimizing The Supremes impact in favor of asserting the name and appeal of . A disgruntled 'Florence Ballard' began drinking and her behavior became erratic both on and off stage. The hits kept coming ("You Keep Me Hangin' On," "Love Is Here But Now You're Gone," "The Happening") but there was internal turmoil and tensions. In 1967, two major changes were instituted: "Flo" was dismissed and replaced with (of and The Bluebelles) and the group became officially known as "Diana Ross and The Supremes".
In Imitation of Life, Sarah Jane performed racial deny through vaudeville: instead of her blackness she chose an imitation of life and eventually lost her mother. In this case, a further parallel is created between the films themes and Diana Ross & the Supremes: The Hollywood Palace represents the theatrical vaudeville and – like The Ed Sullivan Show – transposes this onto television. Diana Ross and the Supremes then do not perform whiteness; instead they become the site for a negotiation of racial and class binaries.
Their name was changed to Diana Ross and the Supremes in 1968 after Berry Gordy fired Flo. So technically their songs under this tag should be from 1968 until Diana left the group. Then it was changed back to The Supremes when Diana went solo. So no they should not be merged. 
The greatest girl group ever had its origins in the late 1950s in Detroit's Brewster Projects. At the beginning the girls formed a quartet and named themselves "The Primettes", achieving mild success locally and recording a single for the Lupine record label. They ended up being a trio in 1960 shortly after they were signed by Detroit-based Motown, a record company founded by . At Gordy's request, the trio formed by , and Diane Ross became The Supremes.