it depends on how big of a plant you want. they will at least double sometimes triple in size in the 1st month of 12/12. my 9" plants ended up at around 2-2-1/2' when they were done. if you're gonnna take cuttings do it now and flower in a week and a half 2 wks
i think it will only bud when mature enough so see no reason not to 12 12 it. have an idea that nodes stay closer but i mostly messed with clones.best of luck man.
I started 12/12 at like 6 inches... they're budding beautifully for the limited space and light I have. Also, they almost doubled in size in the first week of 12/12
I started flowering after 3 weeks of 18/6 due to size on my grow cab. On my first grow I flowered for like 6 weeks and my plant reached over 7 ft tall...