If you get lean, your maintenance will be lower while you're losing fat than it will when you stop losing fat.

There comes a point during the advanced stage of fat loss where your body will begin to fight your efforts.

It wants to retain fat.

Fat is useful to the body for survival, and you are telling your body that food is scarce. Your body thinks you are in a famine.

It will even prefer to burn muscle at this stage, as extra muscle is calorically expensive tissue that can be sacrificed.

To maintain muscle, you need to ensure you're getting lots of protein, and lifting at a high intensity (lower reps).

Your maintenance at this time is NOT what your maintenance will be when the diet is over.

You will be able to eat more without gaining fat.

During the "famine" your body is down regulating NEAT (non exercise activity thermogenesis) - calories you burn without thinking about it.

You'll find it hard to talk as fast.
You will feel colder.
You won't roll over in your sleep as much.
You won't wave your arms as much when you talk
You'll become lazier
You won't tap your foot while you sit at your desk.

When you come out of a calorie deficit, some of those extra calories will just go towards up regulating NEAT to normal levels.

All of the above things go back to normal.

So while you're in the diet, you might have to eat below 1700 calories to lose weight.

As soon as you come off of the diet, you might be able to maintain at your new weight on something more like 2,000 calories - just because NEAT is upregulated again.