Auto/photo doesn't really change the principals of growth. You can push your plants to around 2000 umol of photons before it starts to curve off hard but thats just light. That given all things are equally rapid you can get 2 + inches per day.
But this requires all 9 cardinal rules of plant growth are met in equal proportions. Plants are a complex circuitry of processes if you increase photosynthesis, perspiration will increase as will water intake/uptake, once you start pushing your plants hard the humidity will lol RealPlayer take off which is problematic in a grow space without excess ventilation power. This gets out of hand during flowering.
The answer is rhetorical, how fast do you want your plants to grow is the question.
If you would like more knowledge o would recommend watching Bruce bugbees videos on YouTube regarding the cardinal rules of growth, high level lecture quality Information on the cardinal rules. Peace ✌️