It is a bit of a journey, and i guess it depends how well you can process situations like this but the only advice i can give about the anxiety that is created is :Hi all, new to the forum but have been reading this for a while.
There does seem to be different levels of anxiety the closer to pick up, just interested how much worse it gets, I'm still at the stage where the car is in the country but hasn't arrived in adelaide yet, so to see people have days and times locked in (however tenuous) seems like I still have a long way to go...
Let it come
Let it be
Let it go
The anxiety in your head makes no difference to when the car will be delivered, but it can change how the rest of your day goes. Its your choice how you react.
It gets better (or changes level) at each milestone and you learn to accept whats going on. Then you get a delivery date but in the back of your mind you are now open to the possibilty that this too will change so you just smile and wave
It gets easier as it goes along. You are on the last lap, hang in there, you are nearly there!