1 gallon containers are pretty small for elder mothers.. unless you get into root pruning and adding more soil etc. id say that combined with the 24 hrs of light is causing the stress.. i dont know the science behind it, someone else can chime in, but the dark period is supposed to be when the plants "sleep".. they use the dark period as their trigger to flower.. once that hits close to 12 hrs they begin flowering regardless of the length of daylight hrs.
I'll chime in here:
Here is how the flowering response occurs explained at an intermediate level (leaving out specifics).
A protein called phytochrome mediates this response. This protein can exist in two
states.
The first state is called Pr, the second is called Pfr. These states differ according to what type of light they absorb.
Pr absorbs RED light and upon absorption changes states to Pfr.
Pfr absorbs FAR-RED light and upon absorption changes states to Pr.
So Pr wants red, and yields Pfr
Pfr wants far red and yields Pr.
Sunlight is very rich in red light, so throughout the day Pr will be converted to Pfr by this light.
Overnight Pfr slowly reverts to Pr (the "ground state" of the protein) without input of light.
Pr is an activator of the flowering response.
Protein kinetics often are such that before a protein becomes active, it must reach a certain concentration. If there is not a long enough dark period, the Pr never reaches a concentration that begins to activate flowering.
Nature takes care of this in a few ways. First, nights get longer as it gets closer to flowering time. Second, as it gets closer to flowering time the angle of the sun through the sky is changing such that more far-red light is produced near sun down (which increases the initial concentration of Pr before darkness sets in).
There have been experiments where plants are given say 18 hours a day of light and then blasted by far red light of a specific wavelength for a bit at the end of the light period to rapidly convert Pfr to Pr. This gives the ability to do more photosynthesis in the plant while flowering--these experiments are generally successful though there are some exceptions.
In addition to all of this, Pr/fr are thought to play a role in circadian rhythm for the plant--the theories on this are more biological in nature and as such are not really my forte. I'll leave the exploration there up to you.
Phytochrome does all this by altering gene expression in the nucleus. It is know to interact with transcription factors which are proteins responsible for jump starting DNA translation, which is a step prior to protein synthesis--nearly all cell signals result in the activation, deactivation, production, or dismantling of a protein.
It is also thought that phytochrome acts as a kinase which is a special type of protein which acts as an activator/deactivator of already existing proteins--often times a celluar response happens according to a chain of kinases activating each other in a row to create a response at the end of the chain--with many regulatory checkpoints in between. Some kinases even activate (phosphorylate) themselves! The mechanism for Pr kinase activity is unknown.
I hope this helps.
Ultimately the answer is this--it's difficult to know what's going wrong. 24 hours of light works in practice, but it is not natural--and we do not understand exactly how all of this stuff is working, even in the most studied of plants (like Arabidopsis)--let alone a very scarcely studied plant like this one. Because we don't really understand this system fully, there isn't much to be said definitively about what it will do under conditions which are not the norm (24 hours of light). We barely know anything about what it does under natural conditions if we keep this in context of the complexity of the plant.
If you're doing something unnatural to your plant, and it's kicking back at you--that's a great place to start looking. Is it possible that you are hitting it with an extreme amount of far-red light?
As someone else mentioned this could be a problem with getting root bound. If the plant senses its running out of space to expand, it may flip on certain transcription factors which are unrelated to photoperiod to get ready for flowering as quickly as possible once photoperiod allows due to the limited nutrients and space for growth available.
This is something which is observed in other plants, I see no reason why cannabis can't follow suit.
Good luck!
