Hey pal.
So, why are you using a 600w in veg anyways. That's madness. What a waste of money. (,unless you have a dimmer)
With autos, a full spec is better from the jump.
And BTW, the pot that you have your auto in needs to be uppoted, as its gonna flip and be supersmall. I uppotted 2 of my autos 2 late and they flipped much earlier than the others. (Well that's I think)
I see you have a leds there. Put that 600w away and turn them leds down do 25-50% from seedling to late veg at 45-50cm.
Good luck pal