12/12 will work, it's just that there is a lot of potential being lost.
It's useful to think of autos as "on the clock" and by that I mean once the clock is
started (bean is germed), there is "x" amount of time in veg and "x" amount of
time in flower, period. They aren't "flipped" by light changes and the clock can't
be slowed or paused. So what you give them during that time period is what they
have to work with. So you're trying to maximize effect within that time constraint.
When it hits the mid 30's (days) it'll start pre-flower on it's own, it will continue to grow
vegetatively until early to mid 40's then it will stop veg growth and go into full bloom
then somewhere between 65 and 85, it'll be done....some finish faster than others.
Generally speaking.
So it's actually a challenge because the fewer mistakes you make, the more potential
will be realized.
With photos, you can veg all you want by leaving the lighting on and you can "prepare"
the plant for the flip. Here, not so much.