how far into flower can plant be and still be turned back into veg cycle?

seeds got mixed up,sprouted a dozen,put in 6" dirt pots grown a few weeks then cuttings taken, and put into flower for sexing. not all cuttings survived. the plant that smells the best and shows the best stature is the one I really want and the cutting didn't survive.

They have been in flower 4 weeks now, and I would like to revert the best one.

Will this work or is it too late? I could post a picture