In simple terms, the Red is more for making quick thin crust pizza (romano style) run at 720°F whereas the blue is better for thicker rimmed (Neapolitan style) run at 900°F.
You can use red to make neoplitian pizza it just a stronger flour so works better in the summer. I blend red and blue in the summer when its hot so the dough doesn't fall to bits when proving.
Apparently.