Free ranging is very good, but has nothing to do with when they lay.I thought that I put a light in there which comes on five in the morning and goes off at 7 at night. They can go outside as well.
Extended light does have an effect, so the answer is more likely that she simply isn't ready to start just yet.
Most of us don't provide artificial lighting, but that is definitely a choice. Artificial lighting will extend how long chickens lay during the year. Those who don't provide artificial light allow our hens to rest for the winter.
I have several Buff Orps and love them. She's a pretty girl.