Just a thought but I wonder if the change in the lease extentions policy might be Motability wanting to limit their financial exposure to electric vehicle battery issues in the future. Most manufacturer warranties last between three to seven years, depending on the manufacturer so limiting the lease period to 3 years removes any financial eposure to a battery replacement. I would imagine that a battery replacement wouldn’t be cheap.
Battery warranty is quoted seperately to the vehicle warranty and is on average 8 years.