pics included, need help with flowering plant

This late ino the flowering period i would not be so worried but i would say that it is prob a phos prob but gow them.if i was you i would take the couple of effected leaves off,then flush with a ph of around 5.0/5.5 lushing is not just for the final weeks and i think that alot of problems could be arradicated.if people got into the mind set of flushing at least 3 times during veg and 4 times including last one there would not have no where near has many problems.

We believe that this is a heat burn or exterior trauma... Heat burns traditionally happen sporadically around the surface of the leaf, not in the valleys or veins where the water and nutrients are carried. Chemical burn is also possible from an overdosed foliar spray... *done that* So from personal experience I'm sure the leaves are fine. They're not producing chlorophyll in the brown spots but the rest of the leaf is doing just fine, the color is good and green..

Don't forget your flushing. You don't want to have a buildup of salts or ph problems locking your nutrients out of the roots.