gluconeogeneis halt or slow down

My guess is that the liver failed to produce some more glucose, through gluconeogenesis -- a process that needs to happen at any point of time when the body had burnt all availabilitites, including muscles, blodd glucose and liver storage, and does not get glucose/fructose/lactose/ citric acid /pyruvate/malate from outside. All the enumerated are getting into a cycle called Krebb's cycle and under normal circumstances burn or generate glucose. So, when none of the above are consumed, gluconeogenesis needs to occur through transformation of free amino-acids (fully broken down/digested protein) into glucose.
It is plausible that you need to replenish your body glucose before starting a new fast.
These are speculations, I don't think the supervised fasting Science had it all elucidated.