Conversation so far:
What is Fitzroy as related to Robert Walls?
After he retired as a player, Robert Walls immediately took over as coach of Fitzroy, an Australian rules football club
What year did Robert Walls begin coaching Fitzroy?
Robert Walls began coaching Fitzroy in 1981

Question: Until when did he remain in that position?
Self-contained rewrite: Until when did Robert Walls remain coaching Fitzroy?