Hylda Baker and Jimmy Jewel fell out during the first series, and grew to loathe each other until the series finally finished in 1973, never meeting or speaking to each other again for the rest of their lives. It's probable that Jewel found Baker's problems with memorising lines unprofessional (several editions have obvious breaks in recording where scenes have had to be remounted), although this was probably due to her (later) diagnosis of Alzheimer's disease.
In November 1969 Hylda Baker released a vocal version of Derek Hilton's instrumental theme tune (Columbia DB 8644), backed by Geoff Love and his orchestra.
By the time the sixth (and penultimate) season was in the offing, Jimmy Jewel knew he needed to make the series due to his financial worries. In contrast Hylda Baker had actually called publicly for him to be replaced by Ken Platt, who had taken on the rôle of Eli in the recent Blackpool stage version of the show.
Jimmy Jewel wore a hairpiece as Eli, although this was more for character than vanity, as evidenced by the fact he didn't wear one in his concurrent sitcom Spring & Autumn (1972).