Light when to switch to bloom mode?

i'd base it on size of plant. if the footprint is sufficient and in vege, stick to that and save electricity. the bloom mode likely adds some red. red is used at all times, so no harm adding it in vege, if oyu need the extra light or photons... base it on what is needed, and you'll save electricity and still provide as many photons as your light pumps out for the space it hits. Based on your diary, internodal spacing looks fine. So, it's getting planty. If you ever see it get stretchy, pop those extra diodes or cob leds on with bloom switch.