But this seems to be the case for all science engineering and Business.
Here is my conspiracy theory 
Maybe this is a new trend. With a 45+% acceptance rate - I am sure the university has admitted far more than its acceptable quota. So they are not grating specific majors till such time they are confident that the students will accept - before they grant them the major. It is easier to track these than pre-allocate them prior. Now it becomes a first come, first serve basis. The sooner you accept - the sooner you get your major allocated till it gets full!?
Its a tough game to play. But I am sure there are enough in-state students to fill and delta.