Week 2, they are starting to build a good root system and the plants starts growing, the first few weeks are very important with autoflowers, they are on a timer, so make sure the first weeks they have everything they need.
A good mycorrhizae fungi is very important, and good starting soil, autoflowers don't like a lot of fertilizer at the beginning so just use a light mix like soil.
The feeding in the soil is enough for the start, I just give them a very light solution around the corners of the pot.