Some re-pot at week two of flower. I use an organic soil that's pretty hot, and re-pot within a week of going 12/12. Gives the plants a fresh shot of ph balanced soil, fresh organics and more footroom for the impending growth. I also give it a dose of Soil Syrup (humic acid) when transplanting. The roots love it.

I also stopped adding rocks to the bottoms of the pots, so I don't have to pick them out when transplanting. (I line the drip trays with the rocks now...works great, but you have to pay atention when watering.)