Heat and light stress?

That is looking like heat stress to me as well. notice the canoeing of the leaves as well. Overall the plants looking fantastic tough, congrats a successful full grow. 80f is 26c 87f is 30c, try and keep it at or below 80.6f/27c and you should be fine. Could try and increese the extractor fan speed to move some of the heat out, but if the ambient environment is also hot where its sucking in from it won't help to much in that regard. 2000umol/s is high, if you don't have any supplemental CO2 going in maybe cut back on that a bit. Best Of Luck!