how tall will a plant get in a 10 oz container?

^^ trying to make them small wondering if that would work well.

Are you going for sog?

as tall as you let it get.. root lock will kill the plant when it gets too crowded in the bucket. I'm sure you could grow a plant that was 3 or 4 feet in one as long as you weren't too worried about the flowering.
if you want your plants to be a certain size when you start flowering, you are the boss of that. flower from clones, and start them as early as you like.

if you are growing from seed, just keep the lights on in veg for a week or two and then switch to 12/12. they will bloom as soon as they are able.

Are you wanting to grow a bunch of small plants for sea of green or are you wanting to keep a mother small? Small plants use 16-20oz minimum. Mothers don't belong in a little contaner like that at all because it makes them vulnerable to root rot long term stuck in something that small.