Reason I ask is because I’m in week 6 of flowering and I usually water every 2 days but I waited an extra day and a half to let soil dry a bit more to help combat fungus gnats. Will the 1.5 days extra they waited for water hurt flower progression?
There is research about controlled droughting that suggests it can increase the THC in certain conditions.
But usually if the plant is drooping already and has to go period of time without water/nutrients, it can certainly focus on getting some seeds ready instead of producing alot of seeds. Or buds in our case.
So don't over do the drying, there is other options for fungus gnats.
Yes, you probably have decent size pot that can retain moisture long enough.
Againts fungus gnats it's often enough that the top of the soil dries few inches, so the larvae/eggs dry up,
since the gnats lay them in the top soil.