I like to run autoflowers 18/6 from start to finish. Some people run 20/4 or 24/0. I believe that the 18/6 provides the maximum amount of light with just the right amount of darkness for optimum growth. I personally would not go below 18/6. Also 18/6 more so mimics the light schedule of long summer days.
Hope that helps.
Btw plant looks healthy.
Happy growing
Looking good mate! ππ»as your buds start to get fatten maybe try removing some of those big pesky fan leafs for extra light penetration but thatβs just personal preference,good luck happy growing βοΈπ»π