Lower your light by about 6 inches. That should speed up growth and get the pots dryer quicker. Not a good idea to flower a plant in stress so hold of if you can. Yeah flush st the flip is a good idea. Feed nutes right away. Don't let them go hungry after the flip.
How high is the light above the canopy? They look better than before. What is the temperature? Old damage won't get better but the new growth should look ok.
I 2nd spider mites. Shine a bright light on the underside of the leaf and look for tiny moving dots. You could also have an mg problem but not enough info to make a guess.
Good luck grower.
I wouldn't like to have something in my tent without mains isolation. Touch a fan lead and see how high you jump with a non isolated version. There are plenty of cheap options for a 12vdc feed which are isolated small and low cost.
Price gouging is common with new devices in the semiconductor industry. That's why vero29 dropped around 10 $ recently. Prices would be double again if it wasn't for competition from china. I never buy the latest greatest new tech thing
You can lst into flower without problems. Just be careful when they start to flower as the branches harden up anf break more easily. Leave the leds up they do work better than cfls.you probably have enough light for 1 plant but try and get another 5 cree a19 9, 5 watt bulbs and keep them all close.
You must have very soft water with an ec if 0, 1. Your ph is high and I guess this is simple ph lockout. Ph your feed/water to 6, 5. You probably don't need calmag maybe just Mg if you still showing deficiencies after a week or so.
Just dissolve the pill in some water then add till the ph is at least 5.5, 5.8 might be better in case it drops again. Hopefully there is nothing bad in the pill