I am using an 8 frame brood box. Upon last inspection I see that the girls have multiplied nicely and are going strong. I have about 3 frames left to fill with brood. I know that the bees fill the used cells with honey, pollen, royal jelly so should I just leave these frames in the lower brood box and add a second brood box on top when all frames are full in the lower? or keep one brood box and remove used frames and replace with bare frames which doesn't seem right. I don't want them to outgrow their home and spring is right around the corner here in San Diego. My research doesn't answer this question of what to do with a full brood box. Thanks!