This is where the student, and many posters, are losing me. When I am on the phone with a doctor's office, they may say, "I have 8:30 or 12:00 available." I would then reply, "The 12:00 works best for me." Usually, the receptionist would reply, "OK, I have you down for 12:00." When OP said she had 8:30 or 9:00 available, why does that mean the appointment is made? The OP never said, "We will see you at 8:30 or 9:00", so why would anyone assume the appointment is set? I have never heard of someone offering two (or more) times meaning the appointment is made in any setting, whether it was a casual get together or a meeting with a teacher. Where from is this assumption coming? Genuine question because I truly don't understand why someone would make that assumption.