Have to be home in time for HVAC appointment

Today, I have a busy schedule at school. I have all of my normal classes, plus I have aftercare from 3:00 to 4:00. What makes me really nervous is that I am supposed to be home by 4:30 in order to meet the HVAC contractor to go over our options for repairing our air conditioning unit or installing a new air conditioning unit. When I called for the appointment, the HVAC representative I spoke with at the HVAC company I called told me that their schedule was really booked up. She said that an HVAC representative could come today at 4:30, but that he would not have a lot of time, and that it was imperative that I were there right at 4:30. At the time, I did not remember that I had aftercare, so I said that this was fine. When I remembered, I thought of cancelling the HVAC appointment altogether, but I really need to get this HVAC issue taken care of before I leave to go out of the country on Friday. I am hoping and praying that the students in aftercare are all picked up early so that I will be able to leave a few minutes before 4:00. My commute home is normally 35 minutes. If I leave right at 4, I will probably be late for my HVAC appointment, and the HVAC worker will leave, and I will not get my air conditioning issue worked out. I am desperately hoping that all of the students are picked up early!

HVAC date