"Early" depends on how long it takes a growing bird to reach prime condition, typically the onset of lay for pullets, a little later for cockerels. Large fowl generally take longer than bantams to reach the peak of condition, but not always. You need to be familiar with the line(s) you are working with. If young birds reach peak condition well before they are shown, they are more likely to molt when stressed, such as when the weather starts going form very warm days to cool nights. Then too, heavy laying production for a period of time will generally take the bloom off pullets, as they draw on their reserves to produce those eggs. That means their feathers start to lose their luster and broken feathers are more likely to occur. On the plus side, I have noticed that pullets often become much calmer when they start to lay. That might be because the feathers are all in, as there are apparently nerves in those pin feathers that don't feel so good when they are disturbed. Other things being equal, you want to see a molt occur rapidly, and the feathers grow back in rapidly. Less "down time" then. The better producers will usually be the faster molters.
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