Update day 65: Exactly one week after switching to 12/12 and they have stretched by about 20cm. The stretch will probably continue for another week and then the real flowering will begin. Both are also developing identically in the stretch. The plants are slowly consuming more and more water and the metabolism will change. By the way, the fan was in the same place. You can therefore use it as a good reference.
At the end of the stretch, I plan to remove the side branches that I didn't remove in the last few weeks of the veg. This will leave only the actual main branches from the mainlining.
Update day 67: Nothing to say
Update day 69: It's day 11 since 12/12h and the stretch has almost completely stopped. The #2 also shows the first pistils. That's why I decided to trim the plant today, as you can see in the pictures. I removed the side branches except for those at the top of a branch or if they have developed extremely well. I also removed a few leaves. I hope that this will allow the lower branches to catch up a little. Interestingly, #2 has developed even better with stronger shoots than #1. I'm not a fan of major defoliation so just a little. Maybe I'll remove more in the future.