Non consitent light cycle during seedling\veg stage

Hey, i know that its extra important to maintain 12 hours of darkness during the flowering stage, tho, how important is it to maintain a scheduled consistent light cycle for seedlings?

For example: Giving it 10 hours of light, 2 hours of darkness, another 8 hours of light and 4 hours of darkness. Day afterwards something else. Does it have to be 18 straight hours of light to maintain a healthy plant or I can give it a 18/6 schedule that isn't consistent?

i always give them diff times in veg but always over 16 hours, somtimes 24/0 the next day 20/4 etc but never under 16 hours so im not sure

shade or indirect light would be fine. i would try to keep it consistent to not stress the plant out. If it doesn't need a dark period in veg why give it one.