Haven't grown many autos, but general wisdom is that plants need some down time as part of the natural cycle. I've heard 18/6 and 20/4 mentioned by most auto fans, some saying that you don't really get more production/weight running 24hrs straight and you're just running up your light bill.
I also remember some weirder cycles - thought I read some grower who went with a continuous 12/6 rotating cycle, another 12/5/2/5 or some such (claimed a real increase, your mileage may vary, lol), but the point being you just need to find what fits you best as you gain xp. If you plan on running autos for a while, you might want to switch up between grows and compare yields, BUT to get realistic/accurate data, you should run the same strain imo.