This depends on a number of factors, plant numbers, grow space, light intensity etc.
With your current light setup tall plants are completely undesirable you need plants with many tops that are short.
If you have 6 indentical square pots in the flower cab, with 25watts per square foot, I'd be looking at 3 weeks veg then flipping to flowering. With 4 plants I would lst and veg for 4 weeks at a push then flower.
I rarely veg over 20-25 days, the plants double/triple in size when you change the light cycle so factor this in too