Conversation so far:
What happened to The Fall in 1980?
The Fall released their fourth single Fiery Jack, their last for Step Forward, on 13 January 1980.
What/Who was the classic line up?
The Fall were formed in Prestwich, Greater Manchester, in 1976 by Mark E. Smith, Martin Bramah, Una Baines and Tony Friel.
Did any other people leave the band The Fall?
Besides Mark E. Smith, all other founding members had left by the end of 1979.

Question: Is it known why they left?
Self-contained rewrite: Is it known why all founding members of The Fall, besides Mark E. Smith, left the band?