There’s no schedule or scale needed. Just establish and follow some reasonable guidelines. I don’t weigh any of my snakes anymore. I feed them larger meals sometimes and smaller meals other times. I feed them every 2-6 weeks depending on the season. All of my snakes are pets only so I feed my males and females exactly the same. I’d feed a 4 y/o BP a small rat every 10-14 days, a medium rat every 2-3 weeks, and a large rat every 3-4 weeks if he can handle that size.