Sensitivity or deficiency?

@Laian Thanks again! Good points. I agree it is probably genetic, I am sure that is why only the one plant has reacted so far. All have been given the same excess light / nutrients. I will go lighter on nutrients next round though and possibly a bit less light as well. This originally did start on the lower leaves but that might have been something else back then. Looking in that pic above it does seem to correlate with the leaves that were praying possibly getting higher light then the tops even. It could very well be that she is showing light stress. I can try raising the light a bit more if it continues to show issues. It could just be wishful thinking but last night I didn't seem to notice much change, hopefully it has stopped progressing. Fingers crossed!

One more advice, how to distinguish between nute burn and light stress. Check what part of plant is affected. If it is only matter of upper leafs, this could be really light stress. If lower leafs are affected even worse than upper, it is definitely nutrition abundance. Don't be confused that other plants are not signalitzing same signs of stress, those are different genetics and lot of time even different plants from same genetics can have different resistance to light stress.

Thanks @laian and @The8thChevron I will double check the ph tonight when the lights come on but last check my bluelab soil ph meter was reading 6.5 and 6.6 across four test points. I moved my lights up a few inches when I did that last top dressing and am now reading 65k lux at the canopy down from 70k lux, I would be surprised if it was light as the other plants do seems happy and I haven't had issues at this light level previously. I would not be surprised if it was a calcium lockout due excess bloom nutrients though. What is the best way to do an EC test in soil? Do I just measure water runoff? Unfortunately I won't be due for a watering for another 3 days now at least.

First ensure the PH is ok. Seems to me like light stress combined with nute burn. Right now make a good flush and you can try decrease wattage.I dont know how are other plants but you said tips are yellow/burnt. Could be light.