2 days above ground tap roots through discs

a small pot. pot-up as it grows. this promotes the healthiest roots possible. if basic watering habits result in a wet pot that stays wet for long periods of time is not ideal for the plant. Water stagnates whether in a bucket or absorbed into some solid substrate. small plant in a big pot is just a bad idea with zero benefits. It's not useful for autoflower either. Anyone that causes shock while potting up should just quit gardening.

It kinda depends on your situation. If you got room to plant it then do so. If you need to juggle a little bit you can also hold off some as long as the root is being kept moist(not damp) and covered from light. Obviously it's best to plant autos asap due to their nature.