I don’t know about other manufacturers or dealers but I ordered my VW Tiguan in November 2021 that was delivered in February 2023 so about 15 months all told.
At about 6 months into the wait I thought it would be handy to add the variable boot floor to my order and was told exactly the same that it would put me at the back of the queue again so 6 months in gave it a miss but still waited another 11 months.
It never used to like this and you could always add or subtract from an order in the past as long as the car hadn’t been built but this seems to be the new world order or if you like straight bone idleness or if you like, can’t be assed.
In your case if it was February this year its not such a big risk if there was a chance of a delay but is it a gamble your willing to take.