White widow

You have covered a d3cent area and got a good shape to her. Pot size is big enough. I'd say its time to flip to 12/12.

If the picture shows the space you want to fill with a fully grown plant, then right now is a fine time to flip to 12/12. When an area is roughly half-filled, it's time. Yes, 38 liters is a big pot. you need about 4L / month and that errs on slightly large size. is it slowing down, or is growth more distributed? It's tougher to ssee when it is spread out vs top colas racing an inch or more per day upward. Did they get taller and you didn't raise the light to match? This can slow down vertical growth, if so. Top leaves look light green, but more than one thing can be the cause of that than just some minimal cannibalization from slightly too much light. if related to nutes, that could slow growth a bit too.

Could be improper feeding, did you notice the purple stripes on the branches? Since it developed during your last 2 weeks and you don’t have cal mag in your feeding schedule this could be a reason. I would add a cal mag product of your choice to your feeding regime at a higher PH since you are in soil 7.0. and first aid give her a leafspray with +-0.5EC 6.0-6.2PH. I always liked to go with big shoes when dealing with soil like you, if you have a high ceiling and space you can give her a little longer veg and get higher rewards in the end. This gives the plant some more time to develope a efficient rootsystem to make complete use of your pot. Your plant will double-triple in size when you flip to 12/12, but still there are some tricks like super cropping, early bud backbuilding to deal with height when things get close Nice plant structure btw👍