Help with deficiency identification

Too much nitrogen, not enough potassium and phosphorous......imo. Does not look like a calcium issue to me.

Looks like your soil ph is to low run a few gallons of tap water thru the soil it will stop

Familiaize yourself with a tool for this, such as KiS Organic's Dichotomous key for cannabis... it covers IPM and nutrient phenomenon

My opinion would be calcium deficiency, possibly combined with some magnesium issues – the brown spotting between the veins and near the leaf edges? Or salt build up and lockup of secondarys. Anyway you got a rather quick genetic. So perhaps don't mind and just push through the last ~2? weeks if it doesn't get too worse. Natural senescence is probably on the way or part of it. Much more important would you pls. check your canopy like NoVC01 said? It looks more than shady and some flowers are looking squished.

Looks like calcium splotches but it also looks like its getting over fed. You monitoring your EC and getting good runoff if its in a soilless medium? Light burn looks diffrent to me but that could also be it.

Try light burn. Have you forgotten to adjust your canopy.