When my renewal came up I did ask if I could keep my current car (The AP on my car now is £2,700) – I was told as it has over 20,000 miles and no adaptations I can’t. If APs are no better come October though I think I’ll push for a lease extension.
I got exactly the same response from Motability when I asked about a lease extension (higher mileage than yours and no adaptations). However, once I checked the lease agreement and noticed that it included a reference to lease extensions I challenged them on this decision, saying that they couldn’t vary the terms of a lease without consent or notification with an option to terminate the agreement. They agreed to the extension although, in the end, we didn’t need it as we found a suitable car.