Ask International student office. If your mentor cancel your I-20, he/she
still need a couple of weeks to do so. If you are married, as long as you
get the F2 transfer receipt before you I-20 expire, you don't need to leave
country. But the most important thing is to make sure which day is the end
day of your I-20. It should not be your current date.But usually, you have
60 days grace period to adjust your status as long as you had one.
Calm down first. If you plan to stay US long term, keep your status is your
main focus now. Good luck!