Where the NMSC Application asks for a first choice college, do I have to choose a college before I submit the semifinalist application, and if I do choose a first choice now, can I change my first choice after my application has been submitted?
No you do not need to choose before submitting your application. We were undecided and waited until we were ready to SIR to add a choice.
You are asked to report your first-choice college (to which you are applying for admission) on your National Merit Scholarship Application using the OSA. However, if you are unsure, indicate “undecided” on your application and report your firstchoice college to NMSC as soon as possible.
Yes you can change your choice after you have submitted your application.
Remember to keep your college choice up to date during the academic year. To report your college choice or a change in your choice, log back in at osa.nationalmerit.org using the username and password you created when you set up your account. You will receive a confirmation email acknowledging your request for a change in first choice college. It is your responsibility to ensure your request to change your college choice has been successfully submitted. (Please note that you may not make a change to your college choice until your high school transmits the completed application to NMSC.)
https://nationalmerit.imodules.com/s/1758/images/gid2/editor_documents/merit_r_i_leaflet.pdf ?