AP test questions: Physics 1/2/C, Calculus AB/BC

I have a question:

  1. According to this site https://apstudent.collegeboard.org/takingtheexam/registering-for-exams do I have to register by March 1 or March 15 if the test isn’t offered at my school?
    It says that this is how to register for an AP if it’s not offered at your school:

Contact AP Services no later than March 1 to get the names and telephone numbers of local, participating AP Coordinators willing to test outside students. Prepare a list of the AP Exams you are interested in taking before you call.

Call the AP Coordinators identified by AP Services no later than March 15.