They are still in a early flower phase too early to estimate.
As others have suggested, scrog so you can even them out nicely under the lights to gain full coverage.
Basically if you use a 600W but are only covering a 300W area you will get that worth - 50% less.
Ye I looked at the pic again, scrog so they are placed out evenly so all buds are at the same level, lower light accordingly for flower but not too close to risk light burn, I usually stay at 16 - 18" with mine. Give them something for flowering to boost it, calmag some bloom boost give em an UPPP
. Add some tin foil to that wall seems like it doesn't reflect much light.
I would suggest keep humidity low 30-40max - I sit on 35, the lower the better less chance of moldy buds. I hope you are giving them some air movement like a fan or a well ventilated area.
So basically all get equal light all get equal energy therefore yield will be at least in the average based upon the strain you have selected.
So when they say you can get 400g from a indoor plant don't expect that on an average level, most seed venders put a High average not the true average just to sell their products. This does not mean you can't get 400+ g you can from 1 plant indoors but it's based on alot of factors.