Stretch or not yet...

depends on context. "the stretch" or referred to as a specific event refers to after you flip to light schedule for bloom phase. Some equivalent exists for autoflowrs whenver an equivalent shift in production occurs. stretching occurs if an area of the plant is in low light... the internodes will lengthen to reach for light. i'm not a plant biologist, but i think 2 factors are at play as to why the plant "stretches" so much after flipping phases. First, rate of growth is an increasing rate (up to some limiting point). So, the fact it grows faster after flipping is kind of expected to some extent (no stretching needed). two, there's a much longer dark period, which may increase stretching of internodes even if light is 150% more intense over 12h vs 18h. So growth continues to increase and limbs stretch a bit longer. I think axillary growth may increase?