After you unbox your land you will know its exact location and you won’t be able to change it. If you love your plot location, great, keep it! If not, you can always sell it on the market. But we would advise you to think before selling, since any plot could be worth much more than a good location. Any plot in any location could hold a huge deposit of gold or other valuable resources. Unpacking won’t show you the quantity or type of resources the plot deposits. To get this information you should send your worker to the plot and explore it after the launch.
The region and coordinates of it will be specified at the very moment of unpacking.