Okay, here goes.

1) Don't toss that sifted stuff yet! Store it in a separate bin with a carrot and wait 2-4 weeks for all the eggs to hatch and the younguns to become large enough to see/sift with a regular screen strainer. Patience is essential.
2) If you want to start running staged bins, here's what *I* do:
Beetles all go in one bin of fresh bran.
A couple of weeks later (usually when the substrate begins to have visible movement on close observation), I move them to a new bin, removing dead beetles as I shift them over, and set the first bin aside to hatch.
I do this a couple of times so I have multiple 'young' bins of different ages and the beetle bin, which continues to 'lay and move' every few weeks.
The bins of worms continue to hatch out and grow--I date the bins by when the beetles left, so I have a fair idea of how long until pretty much all the eggs have hatched--and if necessary, I split those bins when they are too crowded. (Too crowded: surface covered with larvae and the substrate is full too). Just take half to a new bin and fill in with fresh bran.
I take the largest/fattest larvae and give them their own bin, according to how many beetles have gone legs-up in the meantime, and let them pupate. You *can* leave pupae in with the worms, but you will lose a fair number to various things. Pulling the pupae into a container with a small amount of substrate and a carrot chunk to hatch works very well and the loss rate is MUCH decreased.
So at any given time, if I get it right, I have several bins of hatching, growing, and pupating larvae and one (or two, I like backups) of actively laying beetles. Numbers-wise...hm. About 2,000 beetles are 'about right' for a large Sterilite container that is deeply bedded. That generally gives me in the (very very general) neighborhood of 10- 15K larvae if all goes well, leaving beetles in there for about a month in warm weather. From each bin, I yank probably 1000-2500 for breeding purposes/beetle replacement, and the rest can be fed out or frozen at the size I need.
Hope that helps! And do, please, do the work of reading the WHOLE thread--there's a LOT more good info and suggestions there.