Take it slow.
Everyone is excited about their new birds coming into lay, and understandably so. Most people are very careful to adopt a feed schedule that will achieve maximum growth and maximum production. What happens with the "maximum" approach is that some late bloomers can't keep up the pace. They may start laying before their time, and that's when problems crop up. Prolapse, binding, stress induced diseases, etc. Just as in people, burning the candle too brightly will wear you out. When you're young, you can handle a lot more than when you're older and you settle down naturally. When you're young though, you generally don't stop until something stops you. Most of us have the scars to prove it.
Birds live by what you provide. If you slow down their maturing process, you'll have a much happier, healthier, prettier finished product.
Most of our birds don't come into lay until long after the "rule of thumb" stage of 6 to 7 months. It's by design. We slow their protein intake, fat intake, and see that they mature slowly.
They always have access to "low-speed" feed such as greens, veggies, leaf mold and so on. They also have all the vitamins and nutrients they need through kelp, vitamins, electrolytes and other supplements. Just remember that the feed-bag feeding program is geared to maximum results in a minimum time frame. It's like a "Russian Olympic Athlete Feeding Program". If you take two steps back and develop a more natural program that's as simple as adding more veggies to your birds' diet, you'll finish a bird of Maximum Quality rather than Maximum performance.
Over time, every poultry fancier or breeder discovers that birds are about time and patience. They are much like fine wine in that respect. Be as patient with birds as you are with your children. You'll finish a product that you can be proud of, and have a LOT fewer problems along the way.