it all depends on where the light it, if u pull it up your plants will no recieve the proper amount of light and they will stretch towards it.
since you light is close, these plants have all the light they need and will be much more compact as they do not neet to stretch.
the right distance will provide the perfect combination of height and and density, this is your job to figure out by adjusting the light and seeing how the plant reacts over the course of a few days.
pay attention now.
chances are that your led uses even more wattage than is advertised as i have found out on multiple occasions.
but ya these lights emit all usable light for the plant, and it gets what is needs even if your light is farther away.
AND DUDE!!! THESE ARE LEDS!!!, they produce all usable light, and 400 watts is a lot for an led.
move your light way higher, i have a 560 watt veg light and i have 4 months old plants that were about 18 inches tall with about 30 branches each node was only a centimeter and a half apart...
i moved the light up to six feet after that for veg.
you definately want to grow more plants and cover more area.
look up the inverse square law.