By theory gradually lowering the light schedule would shorten the amount of time that flowers started to appear from when you get to 12/12. Never done it, so I’m not sure if the overall time would be any shorter or not. Others leave their plants in 24 hours of dark before starting 12/12 that supposedly does the same thing. You can always give it a try and see.
You can flip whenever you want. If she hasn’t been vegging for 3-4 weeks she probably won’t show flowers right away regardless. After that, you’re really just increasing or decreasing yield potential by veg times.
There was a post from one of the moderators on here just yesterday describing what he does from a lighting perspective… essentially making incremental changes every week or two until he’s down to 12/12… I’ll see if I can find it (don’t hold your breath).
Somewhere on here I found a found a “grow schedule for soil growers”, and luckily I saved it to a word document because I can’t find it again. It shows an 8-week grow schedule, 2 weeks of veg, the switch to 12/12, then about 3 weeks before pistils pop.
This is why I don’t grow or even allow bag seeds into life. There not worth the trouble. I spent over 3 months growing bs males one at a time 5 in total. Then I found out how to order fem seeds online. I’ve been cutting clones for months now and there getting better every time.
6 nodes is more like when to top I may be confusing in my lighting schedule but also I veg my plants longer than it would sound I rotate so usually a plant going into flower is 2-3 months old or since cutting Your plants will grow almost exponentially in veg if topped a few times and given an extra couple weeks once everything is dialled in. Roots established etc keep in mind they produce the energy they need to grow so as they get larger they gain more and more momentum able to get more energy and fuel more growth. An extra week in veg can add up to an extra 1/4 oz or more if they are happy