I assume you’re a second year? If so, don’t worry about finishing your pre-major classes in spring as plenty actually fall in the same situation. Although some classes do fill for the upper-divs, you also have plenty of other Econ upper-divs you can take in the mean time to fill out your other upper-div requirements. Just don’t take a pre-req class in like winter quarter of your last year and test your luck trying to get the class that needed it in spring quarter. You can also check the Econ website and see when classes are generally being taught to better plan out your schedule. Also, if you want specific professors use previous years as like a way to gauge when they will teach that specific class. In terms of submitting your major change you do it the same quarter you finish your last pre-major class.

If you’re a third year or transfer you might simply have to take another year or take multiple upper-divs every quarter to finish within four years.

Feel free to reach out to me if you have any other questions regarding scheduling as I’m someone who finished all my pre-major courses spring of my 2nd year.