Strechy/Leggy

it can also stretch excessively by the difference between day and night temps and if you can get the room to stay at the same temps as daytime at nights the internodal space will be shorter but come on why are you afraid of stretch. its good. big plants, better air movement, less chance of mold etc etc.

You can get stretch from lack of light or to much heat. You have an autoflower so low stress training is recommended.

stretching is fine, excessive stretching is the problem and you can avoid that by giving it enough light from the start. but also dont be afraid of little stretch. having space between your nodes is a good thing. it improves air circulation and buds dont touch each other and grow freely. nothing bad about that. so this is an auto, stay away from high stress methods mostly. supercropping is fine by the way. look up plant chiropracty by kyle kushman. creates thicker stems without stressing the plants one bit. basically you’re supercropping without bending. lst is another friend. based on this plants vigor and health i’d probably tie it down around 3rd week to make the main stem flat supercropping at the bending point. then after side shoots grow 2nd or 3rd nodes i’d start supercropping those side shoots in the same way kyle does, without bending. and basically just let it grow happily and without stress. and also dont obsess about it too much. too much involvement and too many corrections etc always leads to hearthache :) as they say it is just a weed so just let it do what it does best and grow.