Intervenal rust spots. What is this?

Hey guys. This girl is on her 67th day of flowering. Leaves are lush green and are starting to develop these rust/yellow spots. As you can see there is some clawing downwards as well.






The girl is on (a slightly heavy) soil enriched with a bit of guano. I've been feeding just plain water and delta9 for the last 20 or so days.

What could this be? The other lady in the tent is yellowing and its leaves are starting to fall...

Could be nutrient lockout. Perfectly normal for older leaves to start going yellow at finishing time, and to take on a Fall color look. When it starts as spots, scorch, and leaf problems nutrient lockout is very common. Check runoff ph and ec/ppm of your next scheduled watering to see, flush if things are in the red zone. With soil, runoff that looks like watered down tea is about right, if it starts looking like strong coffee, things are too rich and will cause issues.

Buds still look great so don't stress too much. Be thankful they made it even if they finish less than perfect.

Thanks Fletch. Kept flushing for a week and getting slightly colored runoff, which I guess isn't too bad. Ended up jarring the buds yesterday.