请教换专业

孩子被录了 UCLA pre biology. 想进去后就换专业。请问转Economics 或 math/economics会困难吗？

发信问了数学系math/economics，还没收到回复。但自动回复邮件里有下面内容。是不是非数学系的选数学课可能都会有困难到waitlist？请教有这方面经历的。非常感谢！

Lower Division Enrollment If you are on the waitlist for a lower division mathematics course, you will be absorbed into the class at the end of Friday, Week 2 or over the weekend. Please ask your instructor if they are willing to absorb the waitlist. After students are absorbed, waitlists for all courses will be removed. This means that throughout Week 3, students can immediately enroll into a course if it drops below capacity. 

Upper Division Enrollment All students on the waitlist for an upper division mathematics course will be absorbed at the end of Friday, Week 2 or over the weekend. After students are absorbed, waitlists for all courses will be removed. This means that throughout Week 3, students can immediately enroll into a course if it drops below capacity.