It took me about 4-6 months to start seeing a new generation in my tank but I started with mixed sizes and no adults so that will vary. I'm not sure how frequently they lay eggs but the little ones should grow within a couple of months. I'm not sure on the sorting. I just leave all of mine in one tank together and pick out the sizes I want to feed by hand.
I'm not sure if it's a big deal. In my experience they really aren't that fragile and haven't been bothered by much of anything. Just add food and housing and away they go. I eventually added an overhead heat projector because they seem to like the warmth. They appear to breed more quickly with that than they do with plain cellar temps and an under tank heat mat. I have more than I know what to do with now though so I don't put much thought into them other than to keep them well fed.
Yeah my whole colony is just in a 20g long with a screen top and paper towel tubes as housing. Works fine. If she's big enough to eat any of them it shouldn't cause a problem and you can hand pick them. I started with a 600 mix size pack from ABDragons about 2 and a half years ago and have many thousands of them now. No way I could get an accurate count.
They egg sack is rarely seen unless you have a lot of adults..it increases the chances. A dubia colony does take s long time to become established if you started with babies. My ivory head colony took 8 months before I even saw any babies. Some roaches take longer than others to grow and mate. My orange head colony is quicker than Dubia's..
Mirage came out of brumation on April 26. He was doing great. On May 2 he started acting funny. We just redid his tank, and he keeps going into one of his hides. He just lays there. He shows no intrest in food. HELP!