So far so good! You are doing all the right things here: harvesting with the lights off or just before the first crack of dawn if you are outdoor will ensure that any residual fertilizers missed during the flush remain down in your roots, not locked in your precious flowers. As soon as light hits the plants, photosynthesis begins and macronutrients and micronutrients begin their vascular journey up from the rhizosome toward the canopy of your plant.
Should you make the unfortunate decision to harvest with the lights on or with the sun up, you may notice a harsher taste/effect/flavor in your finished product; this is the result of excess chlorophyll and possibly residual heavy metals (i.e. “stuff”). If you’ve ever grown or received product that had a smell like alfalfa or hay or freshly-cut grass, then you’ve likely seen what happens when one harvests with the lights on. The best way to mitigate this issue is to gas off the excess “stuff” from your finished flowers through a prolonged curing process.
The flush has an affect on the cure as well. Be sure to give at least 10 days to 2 weeks of pure water at the end of your flowering cycle, just prior to harvest. This flush process with further ensure that your finished flowers are pure, clean and residue-free.
So, unless you want to “work some jars” and have a super-long cure, I recommend that you harvest just before the lights come on and give a nice, long flush.