There's some yellowing on the outside of your leaves, which you should look in to. Your girls are asking for help.

Your plants are about to explode. Autoflowers have a 15 day vegetative growth before they start blooming. You just exited that, so be prepared for a lot of good growth my man!

I'm not saying 20/4 is -the- way to go. If you're doing 19/5, and that works, keep with it. I've heard of 18/6 working just fine. Feel it out, you know?

5gal buckets for an autoflower? I hope you're only using a bucket or two. Autoflowers grow best in what I've been told is called the 'sea of green' set-up, which is what I have. I'm using an EarthBox, and I have three healthy adult plants, and one that is rather diminutive in stature. However, I think it's because of a bad seed. Anyway, my point is, if you get caught, they count the weight of the soil towards the amount of pot you are growing. There was an article in High Times, if I'm not mistaken, about a woman getting hit with 86 pounds because of all the soil she had. The pigs are vicious, and will try to ream you as hard as they can.

My only concern with your plants, like I said, is the yellowing. Is that -browning- on the tips? That indicates death in the leaf. Get on that.