 Schaeffer returned to run the group at the end of 1957, and immediately stated his disapproval of the direction the GRMC had taken.A proposal was then made to "renew completely the spirit, the methods and the personnel of the Group, with a view to undertake research and to offer a much needed welcome to young composers" .Following the emergence of differences within the GRMC Pierre Henry, Philippe Arthuys, and several of their colleagues, resigned in April 1958.