Ordering 27 Octa

I currently have an order for a 27 Blue Octa. I really wanted the Burnt Sienna leather interior, but choosing it always forces Green exterior. Is there any reason why Land Rover only allows black leather with the blue exterior? Blue and Brown/orange is a great combo. Between the two options, I'm prioritizing the blue exterior to the brown interior, but seems weird I can't have blue w/ brown.