Mid/late flowering dead spots/yellowing. Any Ideas??

So these ladies are in flowering week 7 and I know I'm supposed to see the leaves start to yellow but I am seeing more dead/brown spots than I am yellowing leaves. I'm keeping ph between 5.5 and 6, they are growing in coco and I'm using GH flora series with added calmag. I'm also giving them plain ph'd water every other watering to help with salt build ups. What do you guys think this looks like? Also does it look like the bud is okay on some of the more brown/dark purple areas?

How long until you harvest?

It looks like boron, calcium, or manganese are not being absorbed well (and probably others). Does your soil drain well so when you flush it the water comes out bottom pretty quickly? Something is not allowing your nutes to be absorbed like they were before.... If you flush it really good with ph water of 6, and water runs out the bottom of container, capture the water and test the PH.... is it way off?

Just flushed with ph'd water at 6.0 and runoff was 5.8, and yea the soil drains very quickly!

And I'm hoping just 2 or 3 weeks until harvest!

GH Flora put out a really bad batch recently, many growers all confirmed the batch they manufactured was totally fucked. read here and many other places. http://www.advancednutrients.com/junglejuicegmb/

Maybe you got one of the bad bottles.... try another bloom fert?