Autos are often overthought . They are plug and play ... most will go 10 weeks regardless of breeder harvest times.
They like simple stress free grows .... no complicated feeds . You can use a good bagged soil and run an auto well into its halfway point
( up to week 6 ) on just that soil and ph water. Then a simple top dress of “ more soil “ watered in.
Most autos are wired for about 90 days average of life .... with a couple of exceptions ( like super autos for example ).
Sativa heavy or “ leaning “ autos can run a bit long ( because of the Sativa ) so they get done when they get done.
Some strains can be topped and such, but if it’s your first run with autos I suggest running them as they are , learn the needs and simple grow techniques of autos , then you can experiment from there.