I purchased an ESA for my MS at about the 3 year/45000 mile point. It is good for 4 years/50000 miles.
When does it expire? The mileage part is easy, that would expire at 100000 miles. But my lifestyle has drastically changed, and now I driver perhaps 8000 miles per year, so I expect it will expire after 4 years. I'm sure it isn't 4 years after I purchased it. But, when I that? Is it 8 years after I purchased the car, or is it 4 years after the car hit 50000 miles (during my 3rd year of ownership)?
If the latter, what is the exact date? 4 years after the day the odometer hit 50000 miles? I don't know when that was. Does Tesla know that date? I wonder if I ask they will tell me.