Conditioning is aerobic work. DMR asks for oxygen above 10 percent inside the compost mass throughout, and notes that demand during PPC can climb higher still. Starve the mass of air and the microbes that eat ammonia slow down while wet airless pockets form.
There is also a floor. Below 40 °C mesophilic fungi, the ordinary moulds of a warm room, move in and the compost becomes unsuitable for mushroom growth. Low and slow is not a safe way to stretch conditioning. If the mass is drifting down, correct the air circuit rather than add days.