They start to cease growing new branches and new budsites, but they do increase in size, get bigger, harden up. produce buds.
So yes, they do grow more in 12/12
Bizzy. Look at my 8 week pic's. They just started growing offset nodes. About 2 feet tall. And they are suposed to be a short plant. So plan ahead. If you were to use clones you can force them to flower at any time.