I had my 3 year contract extended to 5 years which was due to run out on 4th October 2023, but there was nothing suitable on the Q3 list, so I got a further 6 month extension until April 2024, so you can get more than one extension if really needed. Fortunately Q4 came up with a suitable car which may not arrive until April, but once the new car is ordered, you keep your current car until the new car arrives.