A 15% ethanol mix is ALREADY required for winter fuel blends. What does this third issue have to do with eliminating the transition to 10% ethanol?
15% mix is called E85. Deadly for most engines not specifically designed for flex fuels. The rubber cannot take this, and the engine temps damage the engine, and the fuel is less efficient so less gas mileage. All bad.
Wrong
https://www.caranddriver.com/news/a15339380/the-vapor-rub-summer-versus-winter-gasoline-explained/