Autos transplant

it's crucial to transplant them when they are still young but have developed a strong root system. This is typically when the seedlings have 3-4 sets of true leaves, which is usually around 2-3 weeks after germination. Gradually acclimate the seedlings to outdoor conditions over a week. Start by placing them outside for a few hours each day, increasing the duration and exposure to direct sunlight gradually. Select a location that receives at least 5-6 hours of direct sunlight per day, ideally more. Ensure the soil is well-draining and rich in organic matter. If necessary, amend the soil with compost or other organic materials to improve its quality. Water the newly transplanted seedlings immediately after planting to help settle the soil around the roots and provide initial hydration. If the weather is very sunny or windy, consider providing some shade or wind protection for the first few days after transplanting.

Typically I try and avoid transplanting autos as much as possible. Its not to say it can not be done, it just I noticed that they are extra sensitive to stress when transplanting and can enter early flower. Autos tend to do whatever the F they want. If I am growing autos I grow them in their main pot, seed to harvest no transplant now. Of the ones I have grown in the past and transplanted. about 50% of them entered early flower. I would say do it sooner then later if you need to do it and be as gentle as you can with them roots. I also transplanted them from small pots indoors to outdoors into soil vs just upsizeing them in the same environment. One last option I have seen is growing them in a container with a bunch of slits/holes in it, then putting another container around that one so it keeps the roots moist and protected, then when its time to transplant you just remove the outer shell and plant the entirety of the 1st container with the holes in the ground and let it explore. This prevents a lot of shock as you not ripping the first container off and disturbing the roots to much. I have only seen this have not tried it in pratice so grain of salt with this advice no idea if its even legit. just looks that way. Good Luck!

At work we move seedling autos outside to the greenhouse after they're about a week old. I wouldn't move them into full sun that young but they can take it at a fairly early stage. If you wanna change pots, do it before flowering starts.

End of veg. When the plant are growing root balls over the soil. It is telling that want more space.