E-10 gas has a shelf life of 6 months. Straight gasoline has a shelf life of two years. Ratings like these are conservative regarding replacement intervals. So, it typically lasts longer than specified, unless it is in severe environments. I've had E10 for the mower, stored in the outside shed (no climate control, but tightly sealed) for a year, that simply would not run the mower where new gas would. I only made use of it after I blended it 50/50 with fresh gas (e10). The fuel in the mower and carb corroded the internals, presumably from the alkali formed when alcohol reacts with water. The mower tank is vented, so it "breathes" all the time, taking in humidity. Yes, it rusted inside the tank, too.
I once had 4 year old gas in my airplane when I still owned it, the engine ran fine. Aviation fuel has an even longer shelf life, though recommendations for replacement remains at two years.
There are(were) conversions for some airplanes to run on auto gas. Those are not certified with any alcohol blended fuel, only pure gas.
E10 will mostly work in automotive situations as long as you repeatedly replenishing supply. Think of it like a shark. Must constantly move forward or it dies. The caveate is for older fuel systems that don't have seals happy with alcohol. Alcohol is a drying agent. Rubber diaphragms (fuel pumps) and rubber seals get hard and crack causing failures, not seen with pure gas. New vehicles designed to run on E10 have seals and part made of alcohol resistant materials. Our vintage bike don't have such materials in stock form.
Most governments think you should replace your vehicle slightly less frequently than you do gasoline. Good for the economy when citizens spend more money, for replacement or repairs.
Cheers,
