Some times if you need something quick then your choices maybe somewhat limited to what can be supplied quickly and for someone joining the scheme that’s what i would suggest looking for and asking dealers about.
If you want something specfic then you may have to wait as everyone does. My current car there was only 3 available in the uk in the spec and colour i wanted back in jan for mid april handover and no build slots the dealer got one of those and held it for virtually 3 months and then covid came along so middle of jun i got it. or i would have had to order something else or in a different color or spec to get it for the handover.
If it’s a big issue not having a car then you need to speak to motabilty and the dealer and cancel the order look for something you can be in in 7 to 10 days.. but it will be for 3 years and i dunno you may need and still want the one you ordered for some reason. Your not actually really a customer yet till you pickup the car and hand over your pin. lucky for me when i first joined my old private car was still going, so drove that around till the nissian qq arrived, which was no more than 2 weeks and was one of the reasons i orderd it.