The AP quoted by Motability doesn’t expressly state the model year, so I would have thought that you should be able to order now and if you get the next model year then so be it. I would question this with Motability tomorrow or try another Volvo dealer. I think I smell dealer BS. It’s standard Motability practice that you pay the AP applicable at the time you order. If it shoots back up £2k by the time you get the car you wouldn’t have to pay it anyway.