Grow #2 - Wedding Cheesecake FF

Dear diary, Week 4 almost done, but posting a day in advance as I will need help from the community! Something terrible has happened, and I am not sure what, so let’s jump into it. 🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀 ⏰ Day 25: Away from home so the flatmate is feeding them from the premixed bucket. ⏰ Day 26: Back home! As they have doubled in size I am transplanting up from 3liter to 20liter airpots. The 75/25 coco to perlite mix was first run with 1.23ms 5.8ph calmag water followed by 1.33ms 5.8ph nutes before transplanting over. Light was about 305 so also upped it to 320-330ppfd. ⏰ Day 27: Feed the girls at 1.36ms and 6.0ph. Today was also the day where the mainlining begins! This was done by topping above the 3rd node, removing any growth below the 3rd and tying them down to start the manfold. Aiming for 8 or 16 tops for each plant depending on how the grow. ⏰ Day 28: Feeding at 1.36ms 5.8ph and adjusted ties. ⏰ Day 29: Checked in on them in the morning before lights off, and something is very wrong. All the older leaves show all kinds of issues like curling, brown and yellow spots, drooping etc. Might just be from the chock of mainlining and the lights being to strong so lowered them to 230ppfd. Later when lights turned on again, their state has not deteriorated during light off, so I’m fairly sure it is light related. But to be sure I also gave the girls 2 liter each of feed to make sure there are no dryspots, 1.36ms 6.0ph. ⏰ Day 30: I was away all day so they were watered by flatmate with 1.35ms 6ph. When I came home later in the night the spots and yellowing is still happening on the older leaves but much slower than before. I also checked runoff and it’s fine at 1.46ms and 6.0ph. ⏰ Day 30: Gave a feeding of 1.46ms 6.3ph in were I increased A and B nutes to 2.5ml/l from 2.0 and calmag to 1.5ml/l from 1.3. Someone suggested that it might be magnesium deficiency so that is why I changed the ratios and increased the EC a bit. Lastly I also gave a foliar spray of calmag water at like 12ml/l at 6.3ph to see if that helps so we can head into a smoother week 5!