Spots on fan leaves. Help a noob?

GG #4- So I noticed some spotting on the leaves that haven’t been there. I don’t see it being a mildew issue, as our humidity is really low here in NorCal, and we have a constant breeze. Any idea on diagnosis and treatment? I Transplanted to the growbag a week ago, but this is the first I noticed the spots or any possible stress, and it’s looked great otherwise. Thank you in advance!

Mark

Check the underside for bugs or any tiny spots. Get a magnifying glass to help