At a heated producer meeting in Ashbourne, AFMP members unanimously passed a motion of no confidence in the chairman and vice chairman.
They also demanded the removal of the word 'partnership' and agreed to seek NFU advice that could lead to them taking legal action against AFMP.
A mass tendering of resignations was also discussed to give grassroots members more say. Other partnership groups were "watching developments", with a group at Settle formally on side.
Members also hit out at the avoidance "through clever wording" of a pledge to give 12 months' notice of price changes through seasonality, and the wording of Arla chairman David Naish's City statement, which talked of "the development of more transparent, market-related pricing". In practice, "there has been the complete opposite".
One farmer source told The Grocer: "There is a huge tangled web of ambiguities in the arrangements that producers cannot understand at all."
Jonathan Ovens, AFMP chairman, denied suggestions that his organisation was in crisis and said he had received just two resignations, with both farmers having checked they could rescind them.
The cuts were necessary, he insisted, because of falls in fat prices. The growth of the partnership meant it had to take greater responsibility for sorting out its own surplus milk rather than relying on the co-ops to "balance" supplies.
He has promised that by September AFMP will issue full details of its pricing strategy and balancing.