Complex sentence: Gaining commercial airplay, a major breakthrough came with the signing of the band by Sony (then CBS Records) to a five-year deal At the same time the band changed their name to "Seven Stories" to avoid confusion with US band Tall Stories.
Split into simpler sentences: Gaining commercial airplay, a major breakthrough came with the signing of the band by Sony (then CBS Records) to a five-year deal. Around that time the band changed its name to "Seven Stories" to avoid confusion with US band Tall Stories.