You can spend as long as you want in Veg with a photoperiod. But just because you grow longer doesn't mean you will grow bigger.
ATP conversion is the engine of growth at a cellular level, factors like genetics, light, and environmental conditions are the blueprints and resources that dictate the size and efficiency of that engine.
Your engine is running slowly. Therefore the plant will not travel far (grow) with its current engine.
Soon as you flip the countdown begins. Equinox won't do shit if there is no ATP to drive any of it.