Let's apply just a tiny bit of logic and and the laws of natural selection to that 'wild snakes' scenario. I'm not saying this is how it is...but it's definitely smart, and nature is often smart.

If the population of ball pythons in an area is high, then the likelihood of young females encountering a male is also very high--so they will breed when they are young and small...and will lay smaller clutches...contributing less to an already high population, and perhaps making it more likely that their offspring will survive when competition for food is high.

If the population of ball pythons in an area is quite low, then females will be more likely to encounter their first male when they are older and larger--and so they will lay a larger clutch, and will have more offspring to eat more plentiful prey items, and survive what might be a higher predation rate.

This makes sense to me.