Dendrob. leaves suddenly losing color and mottling

[RobotPigOverlord]

Update: im fairly sure the issue is anthracnose. The biggest tip off is the fact that the leaves were wasting away always starting from the tips and then making their way down the leaf. Ive started treating all my plants with thiomyl. Im repotting, disinfecting, etc. So far my chrysanthem seems to be responding positively to the thiomyl treatments.

Im surprised because I have a ton of air movement in the room with my plants (large ceiling fan always running medium-high speed, plus smaller oscillating fans), the chrys. is mounted so its not like it didnt dry out quickly every day. However I think the issue was due to a lot of high temp and high humidity days/weeks in july and august. Thats my best guess. Hoping the multiple rounds of thiomyl treatment wont somehow disrupt the flowering that im expecting from the affected cane in the fall 😬