Orange lines on fan leaves during flower

hello I am on day 28 of flower and ive been feeding per normal (no heavy feed yet) but recently a couple of my fan leaves are going orange? This is only happening on the very top leaves, I thought it could be calcium def, but ive been giving 5ml of calmag per gal so it should have enough calcium

rust mold? I don't think so either cause rust mold is much darker

Calcium deficiency