When to swtich in to maintenance mode?

Options
OK, so I'm closing in my newest goal weight. I've changed it twice now. My first goal was just arbitrary, I just picked a number, then I changed it to the top weight on my Healthy BMI weight range, and now i've lowered it another 5 lbs to be inside the heathly range a bit. Should I stay where I'm at my current goal, or should I change to the weight in the middle of the BMI range? I wondering if anyone has any good thoughts or ideas on setting a final goal weight?