I’ve ordered 3 cars this year.
The first was built and got to the port in the UK and was ready to be sent to the dealer for delivery to me , after a 12 week wait from initial order . I cancelled as an AP drop made a higher spec car come within my budget.
You don’t really need to consult with Motability about changing unless you’ve gone over the 5 year limit already. If not then just cancel and reorder with Volvo
I had my previous car 5 1/2 years. As long as you order within the 5 years they just extend until order is delivered.