From what they said yesterday, today and through the weekend is going to be busy for the Birmingham crew... Yesterday I think they said they had around a dozen cars to handover, but today on for a few days at least they're moving into the 20-40 cars a day bracket.
I found the whole thing wonderfully straightforward and simple, so I hope today is much the same.
My advice is just take your time, ask questions, get answers and feel comfortable before you go.
Also, they actively encouraged me to look around, take note of anything not absolutely perfect and to book in with service then and there. To the point where I now have an appointment for service with MK Tesla for some very fine, hairline scratches around the paint of the door handle. Which, if I'm honest, I'm embarrassed that I even mentioned.
Have fun. It's an experience for sure and the car - so far at least - is lovely.