Will depend on a number of factors: nutrition, how young you start breeding them, beans between litters, litter sizes, and the individual animal and her ability to bounce back.

When I bred for pet and show, productivity wad not important, and I only bred females once or twice. They routinely lived 2 or 3 years in good health. Through the progress of my being program I was seeing life span increase, but I doubt I would have seen anything as dramatic as doubling it.

For production purposes, I doubt you'd want to keep enough females to only breed them once or twice. Of course that depends on your needs too. I think giving them a couple months breaks in between litters is sufficient.

Right now I'm keeping about a dozen females, breeding 2 at a time, pairing males and females every 1 to 2 weeks. This is keeping up with my needs (feeding 10 ball pythons and I do f/t), while also allowing each female a couple months break between litters.