No, they'll reach maturity sooner or later, unless they are sick for some reason and die.All of my B. Orientalis sub-adults reached maturity at least 5 weeks ago except for two. Is there such a thing as roaches never fully reaching maturity?
It's not something that was planned. I found a big female in my kitchen last summer after new windows were installed; it probably hitched a ride on some packaging material.Why Blatta orientalis? Did you collect them yourself?