Wow that is absurd for the blue…I had the same decision on my TL, I ordered the car in dark metallic blue just like that (which is a gorgeous color) but ended up settling for silver when I found out it was going to be a 4 week wait.
The good news is gray will probably be easier to take care of and easier to resell in the future. Blue is very hit or miss with most people…but it does look nice.