It is complicated. My daughter recently did this, and it took a long time and there are consequences. Read your contract, exactly what the contract says is what may happen if your PMS recommends a transfer of scholarship. Your PMS can also not approve a transfer and you will lose your scholarship. This is the important part, your school has a nursing mission. A transfer of scholarship means transferring your scholarship to a line scholarship means they lose the nursing scholarship. My daughter was granted this at the end of her sophomore year. The contractual consequence is a one semester administrative suspension. Because she was a sophomore and not a freshman, she was still contractually responsible to the Army, in your case you are not because you are still a freshman, so you are not obligated until first day of your sophomore year. She was granted the transfer, the PMS requested it and it was approved a few weeks into this fall semester of her junior year. My daughter has kept her stipend and book money, because she is still contracted, but we are paying her tuition for one semester and then it will reinstate. Another scenario since you are a freshman is they could just remove your scholarship, so they can keep that nursing scholarship and then you could compete for a campus scholarship. All of these options need your cadre’s support in you as a cadet and their belief you will make a good officer. It isn’t a quick or easy road and there is a lot of waiting. My daughter switched to a communications degree and she is loving it. She will still commission as an officer, and her scholarship will reinstate second semester of this year. Just to get the approval took months and months with no guarantee.
As a freshman you can walk away with no obligation after one year. From experience, if you want to continue with ROTC and have the chance at having a scholarship, do not switch your major or do anything with the school until you talk to your PMS. The bottom line is you need to talk to your freshman MSL instructor and then your PMS. Let them know what you are thinking of doing and ask for options. Understand they will first and foremost tell you they understand but there are consequences. You will need to understand there is a way to get where you want to go but it might not be easy and there may be costs associated. Feel free to PM me once you have the required number of posts to qualify for that feature.