On your NVC case page, there's a message box where they've probably already asked if you'll change your status. You must notify the change of status, but adult children of citizens are further behind than adult unmarried children of F2b legal permanent residents.

I recommend you look for legal support for a decision that favors you.

check the visa bulletin, F2B and F1 have so much of difference with respect to country. If you don’t have much dates difference you can change but better you ask your attorney and take his/her advice before making a decision. Fyi, you can change the category at any time.

if your pd is 2017 or after its best you change it because f1 is going back in front of f2b by next year

Thank you all for your help