Wondering when to stop nutes and start flush

so, you want them to grow / ripen but starve them of the molecules necessary to grow / ripen? law of conservation of mass.. there is no immaculate manifestation of building blocks. keep'em healthy. a much better plan. flushing is a tool to combat utter catastrophe in your rootzone. that's what it is good for and should be avoided with any healthy plant.

Flushing is usually commenced two weeks before harvest. If the plant has an eight-week flowering period, the flushing will need to take place six weeks after the start of the flowering stage. It is best to take a close look at the trichomes on your plant to assess when your cannabis is likely to be ready for harvest. If the tiny trichomes are just beginning to turn from clear, to a cloudy and milky colour, this could be a good indication that the plant can begin flushing. It should be timed so that the majority of trichomes will have fully changed to the desired colour for harvest after two weeks.

There is a difference of opinion among growers as to whether plants need to be flushed or not.... some say they do because they can taste the chemicals that had been used in the nutrients (if you grow organically, this reason evaporates as there are no chemicals!) - but those peope, imho, have overly sensitive taste buds. I don't flush, myself. I used to, didn't find it made any difference, and it was a pain... so just skip it would be my advice. I agree with GMSgrows on the partial harvest... autoflowers really don't like stress and chopping off the top half would be a MAJOR stress that would essentially stop the plant from doing anything more for the unharvested bottom half... Good luck - and congrats on your grow!