leaves dying last week of flower

White Widow
flowering for 6.5 weeks
5 gal Coir/Perlite 80/20
Canna Coco base plus Boost and Cannazym (every other feed) @ 5.8 pH on alternating feed/water schedule.
600w hps air cooled @ 1.5ft
temps at tops 82 degrees F
relative humidity 43-47 (fluctuates constantly)
supplement with CO2 in accordance with manufacturers directions

it started about a week ago with light yellowing of some leaves, but now about 15% of my fan leaves are dying/browing/drying out. flowers are huge thriving. i believe the plants are severely root bound. i plan to begin flushing them the beginning of week 7. would it be worth repotting this late in the game or should i just let them stick it out?

thanks in advance for any advice.

If your just going to be flushing in a few days then no, the added soil will have nutrients.

Hey, i dont grow in coco so im not sure what that absorbs, somone will tell you that, but back to your questions, the yellowing sounds like they are root bound, or are def.
personally, i wouldnt repot now,i take it you plan harvest week8, simply cause you will shock the plant and i would see that as a waste of soil,, sorry coir and perlite, may i ask what size the cointainer is? 3gallon/11ltr? How tall are they? As that would tell us what the plants are like.
Also i have noticed that during the last two weeks the leaves kinda die off anyway, especially during the flush, so i dont think its goin to be a deficiency, but like you say, more likly root bound ness,

Sorry, re read your op post, 5 gallon container, well is it a tall or squat pot?
Well maybe root bound depending how big they are,, so i would then ask is the yellowing the interveinal or complete yellowing(veins and all). Also it couldnt be burn,nute or light?
Like i said as the plant matures past the harvest phase the leaves do natrually yellow and die off, just repeating what i said,,, take it easy.

Coco absorbs and realeases nutes, so it could be that, sorry just spit balling now, Nd taking up post space.

thanks for the prompt responses, guys. they are completely yellowing/browning/dying starting from the tips and moving down the leaves. i figure just let em go. i've had leaves yellow up last week after flush, but not like this. the pots are equally tall as they are wide (or close to it). the plants are short and wide. they have around 40 huge tops each though and the root ball is about an inch below the surface and is thick thick thick. i haven't opened them up, but i do believe root bound. started weeks ago with dying lower leaves (ignored this) then leaf roll set in and now severe yellowing/dying. fits every root bound scenario i've encountered. just wondered if any one has experience transplanting so late, but yea.. i think i'm just gonna let them go.

My fan leaves always yellow in the last weeks of flower but flowers are fine. I wouldn't worry at all.