Can you tell me when does starvation mode kick in?

Evolutions Slowdown: When you drop your average daily intake below the level of your resting metab rate the avg is 14 days until starvation mode kicks in. The first seven u will feel hungry and tired, & u drop weight. But this is a good way for body to try and conserve fat. The next 7 days the body usually holds onto the fat(starvation mode)& even though u do the same as 1st wk much less is lost, 3rd wk it evens out.