Hi and welcome to the Forum
Unfortunately, car manufactures do have small print stating they can change specifications, by adding or removing items, and the longer your wait for the car the more chance there has been changes.
The one area you do have control of, is if there is a big cost difference between ordering and car arriving, you can reject the car, by saying I did not want this and cannot afford this.
I have had former experience of this problem by waiting a whole year for a new car. I was desperate for a new Honda Civic Coupe in 1993, it was made in Ohio USA and exported in RHD to UK. There was a long waiting list and my 5 month wait ended up being one year. Never again will I do that.
When the car arrived I had problems over changes and hence costs....
1.....They had added a built in engine immobiliser at £300 extra due to spec change. I argued the case that I did not ask for the immobiliser ,but they told me pay up or cancel the sale. So I stumped up, but I wrote to Honda UK head office saying i had waited a year for this car and did not expect this situation, and they paid me the £300 back .
2....Honda dealership tried to charge me the annual price increase, even though i had agreed a price a year before. I totally refused to pay this as I had waited a year, and they had to accept this, cheeky blighters.
Covid 19 problems....
Another problem is that Covid 19 is causing supply parts shortages or delays, and some cars have had items removed from spec or changes made to complete production. My Sister who ordered a Renault Captur recently, had switches missing when it arrived at the dealership, and the dealership asked my Sister if she would take it and the switches added later, and she said NO, as once you get a car off the dealership and money transacted, they forget about you. So she waited another month till the switches were added to the car, and she then got it.