affects the plants if I change the photoperiod to ...

Auto fruit doesn't matter I leave mine in complete darkness for 48hrs before cut it is proven to enhance the potency of your trichomes and terpines etc.

Why would you if it's an auto?try reducing it slightly maybe to 18 or 16

It should not stress the plant out, you may even get more trichome development. At this point your flowers have pretty much finished developing.

I would say so the 12/12 and add more ref lights if possible you will get more crystals

Hi there mate Dropping back to 12/12 from 20/4 won't really have any major effect on your plants Like bulbi says less light stress etc There is also some research that suggests dropping the lighting hours can also help quicken the harvest time Which could be of benefit 😀 Hope I have helped

Hey there mindoor, the light schedule will affect the plant, but it wont be so bad, you're already at the end of flowering, so if you switch to 12/12 the plant will have less stress, less light less stress, so it will produce more terpenes and THC, but a bit less yield. If you need to flip then flip, it will not harm your plant in any way. hope this helps ! 🚀

12/12 is the flowering light cycle