Conversation so far:
Let's start with...what does Former have to do with Serebro?
Despite original indications that Serebro was for a solo singer, it morphed into a group around the former Star Factory participant Elena Temnikova who was paired with two newcomers.
Who have been members of the group Serebro?
Serebro's members have included Marianna Kochurova, Marina Lizorkina, Elena Temnikova, Anastasia Karpova, Dasha Shashina, Polina Favorskaya , Olga Seryabkina, Katya Kischuk, Tatiana Morgunova, Irina Titova, Elizaveta Kornilova
Why did Elena leave Serebro?
On 15 May 2014 the official Serebro website reported that Elena had left the group due to ill health.
Did Polina stay with Serebro for long?
Polina Favorskaya announced she was leaving Serebro in August 2017, but continued performing with them until the end of 2017.
What is Polina's birthdate from Serebro?
21 November 1991
Who else had been members of Serebro besides Polina Favorskaya?
Anastasia Karpova
What is Anastasia Karpova's birthdate from Serebro?
2 November 1984
Did Anastasia Karpova stay with the group Serebro for long?
Karpova decided to leave Serebro to pursue a solo career. The song УГАР was her last song with the group.
Who else had been members of Serebro besides Anastasia Karpova?
Marina Lizorkina
What is Marina Lizorkina's birthdate from Serebro?
9 June 1983

Question: How many former members were there in the band??
Self-contained rewrite: How many former members were there in Serebro??