My uncle harold used to take his newspaper in the bathroom and stay there for sometimes 1 1/2 hours. Maybe your chicken is just taking a break like my uncle harold did. But, if your chicken is producing 6 eggs a week she is being more productive than uncle harold was. Sounds like she's doing just fine.
That would work for me. As long as they appear to be healthy, eat and drink ok and make good eggs, they can sit in there all day for my money. I do have one broody gold comet. Don't care. She just wants to be a mama more than the others do. She lays her eggs too and eventually leaves. Have caught her trying to keep 4 eggs and a golf ball warm. I put all the golf balls in one nest to see if she would fall for that, but she did not.