Does any of you guys know whether or not a shorten...

At this point it wont affect the size of the plant , but I also dont recommend going anything less then 12 hours a day of darkness/light because you still wanna follow the plants general life cycle . A photo period plant is far more dependent on the amount of light it gets to control veg/flower with that being said usually people will go 18-6 for veg and 12-12 for flowering . A auto strain doesn't need that they are designed in such a way that you can leave the lights on 24 hours a day and it will still flower and finish strong . So ultimately there are a few guide lines you still wanna follow like having atleast 12 hours of darkness during flower but for the most part people just leave their lights on 24 hours a day when growing an auto . I personally never run my lights 24 hours a day for any plant because to me its important the plant has a rest period of minimum 4 hours but thats a personal choice when growing auto's it isnt necessary . This applies just the same to the veg cycle of your plant you dont want any less then 18 hours a day of light for any plant to have more is okay but to have less then that and your plant starts to think the seasons are changing and it also wants to change . Provided your light is close enough and you follow the regular guidelines you would follow growing a photo period plant your auto strain wouldnt be any smaller then the next . I hope this information helps you understand how a plant grows and the various light times you can have with the small guidelines that are standard in todays growing . -Happy Growing!