Tesla uses Just in Time manufacturing process.
This means they don't start getting supplies to build you car until after you order it (for the most part).
Once you order, you go in the queue.
Then a Tesla makes cars in batches, according primarily to final destination
They batch all the European cars together
Then they do East Coast of US
Then Midwest
Then West Coast
Then California
The do this because of shipping times (takes longer to ship to Europe than US)
Most of the cars made for Europe this quarter were made in October or early November and then take 6-8weeks to ship.
Tesla just finished the Midwest this week and is now starting on Californians
They will make the next batch of European bound cars in January, which will deliver 6-8 weeks later. Hence, March
If you didn't order your car in October or earlier then you had a glitch, and your car probably hasn't even started production yet