orange rusty color on top

Feels like a PH issue to me, but natural fading/lockout could also be it. your EC is quite high for an autoflower grow to me. I try and keep it in line with these numbers https://www.autoflower.net/forums/threads/med-man-method-feeding-chart-ppm-ec.47856/ Your very close to be done and this would not affect your end yields by mush is anything at all. I would keep up what your doing and lower your feeding solutions EC like down to 0.5 Best Of Luck & Happy Growing! ***disclaimer, multiple people are answering all questions as there is a contest called GOTM, when a user is selected as the answer they get a point. Please see the contest page for information regarding the details: growdiaries.com/giveaways/GotM-August-2022 Please note, when you reply to anything on the questions part of Growdiaries website, no one will be notified of this. Not even if you use a "@" tag in their name. Best to reach out to them in DM using your inbox, it can be found in the bottom right hand corner of the site. It's the small paper airplane button, it will be highlighted green if you have new messages***

Looks like a tasty bud that's close to done to me! Happy harvest!

heh, first guess was gonna be light. pH proper? At this age, senescence is a possibility too... simply the plant nearing end of life and drawing down leaves. it's chlorosis and at the top (immobile) with some bronzing it'd be rare but are you watering with something that has large amounts of chlorine in it? maybe, excess iron? Boron deficiency? the thing with these trace elements is that they are very rare in soil and more indicative of a pH issue.

I think your ladies are saying it's beginning to die naturally... and that you should prepare for your time in trim jail... Have you taken a close look at the trichs? This will give added information on which to base your decision of when to chop them... But seriously, everything looks fine with the conditions you're providing - and, being autos, they're about at the end of their lives... Good luck!