In reality, plants should never be grown at 24/0 or under continuous lighting. It is so very unnatural and stressful for them.
18/6 is the optimum lighting schedule for both autos and photoperiod plants in vegetative growth. You will gain very little by running your lights any longer than this, but your plants will be much healthier if allowed to have a normal circadian rhythm of grow/sleep/grow/sleep etc.
This could be one reason why your plant is yet to start flowering, being in a constant state of "awakeness" might have led to a hormonal imbalance that has then caused the plant to not have the correct "information" that it needs to signal that flowering should begin.
With your other flowering plants, wait until there are approx 90-95% brown pistils for a more mind expanding head high and for all the pistils to grow brown if you prefer a more heavy and sleepy body stone.
Also, if you grow any photoperiod plants rather than autos, you will have to change the light cycle to 12/12 light/dark to initiate flowering in those plants.
It is never a good idea to mix autos and photoperiod plants in the one grow, - your photoperiod plants won't flower at 18/6 and your autos won't yield much at 12/12.
So, go to 18/6 light/dark and your plants will be much happier and more importantly healthier. Wait for the pistil colours to change before harvesting at your preferred effect type and never rely on what is written on the packet, it is only a guide and not strict rules. There are far too many variables involved with growing that not one single set of instructions will cover everything from a full hydro set up with multiple HID lights to a dude growing in cheap potting soil and using a 30 watt blurple light in a cupboard.
Usually with autos, it can take from 2-6 weeks longer than claimed on the packet, with very few ever being ready in the claimed timeframes.
Also, never grow plants at 24/0, it really stresses them and would only be recommended by people who either don't care about the plants or have a complete lack of knowledge as to how plants function and grow. Sleep deprivation is a common torture technique and is used for good reason, it drives people nuts, much the same as how your plants are no doubt feeling now. I am not blaming you, I am blaming the person who told you this is OK for plants.
Your plants will grow just as much at 18/6 and be far healthier too, which means the flowers will be better quality too.
An exhausted plant can only produce exhausted flowers, and not the prime quality of a plant with a normal pattern of grow/sleep/grow/sleep.
I like to think of the 6 hours of sleep as 2 hours to recover from the day, 2 hours to rest and 2 hours to get ready for the day ahead, and this is basically what occurs while your plant is "sleeping". Everything living needs sleep, without it, things go wrong very quickly.
The good news is that it is never too late to change your timers and help your plants recover their health. I guarantee that in 3 days time, you will notice a difference in your plants, and they will just "look better"!
Good luck and happy growing!
Hope this helps,.............
Organoman.