Time in sleeper berth?

As with almost everything else in this industry, there is no one size fits all answers. Your line 2 time after 10 hours will depend on your load and how much time you have. It's 4AM CT and you are 30 minutes out of Chicago, you know you are going to have to go through Chicago. No driver in their right mind is going to subject themselves to that traffic by just staying in the bunk or talking a walk. If however, you are laid over or maybe getting a 34 in you will in most cases stay in bed. I would advise any driver to stay as close as they can to their Circadian sleep cycles in regard to that sleeper. Common sense will carry a driver a long way.