For what it’s worth, I think the issues I was noticing were possibly caused by scale insects. I noticed these bastards when watering one day. I suspect the yellowing and dying leaves on my plant were because of these sapping the nutrients out of the stem. Still an ongoing issue for me. 
I started noticing burn when I uped the nutes to from every other day to full strength every other day and half strength on others so I pulled back to every other day.
I did have issues with the top leaves getting lighter kind of similar to this earlier in the grow because of air circulation issues.