This week the pots started to become a bit small.
I guess you could have let them sit in the small pot for another week or so but had taken a quick look at the roots because of the whole leaf situation and noticed that the roots were already starting to grow along the walls of my pot.
So....
I decided to transplant them in their final 11L fabric pots at day 18.
Since the plant was developing some nice side branches i began with the LST at day 19.