Yep, you don't really have to wait for a 24 hour cycle. I prefer 18/6 though. I believe the plant having time to rest is beneficial although there's very little science regarding this.
I tried 24h on auto's but found to get better results with 20/4 or 18/6.
At the end of the day they can take morr light and use the night time to perk right back up.