The transition from kibble to raw can be long and challenging, we recommend a very slow transition. The primary reason for this is to avoid upset stomachs but primarily because rejection of the food is to be expected. Give your cat the time and space they need to figure out their new diet. That being said, you do not want to leave it for more than 24 hours without eating something. Cats need to eat frequently as fasting is unnatural to them and could induce a case of Hepatic Lipidosis (feline liver disease).
Find our transition guide for cats here: Transitioning to our Big Dog Raw Diet for Cats