Time not well spent sitting around staring at the telephone waiting for phone calls. There are part time jobs that may be available out there but they will remain hidden if your job focus is so narrow that phone calls for substituting opportunities is all you wait for. Hoping that your "freaking out" was only a literary device to make your posting more interesting. The students need an adult in the classroom that will give them the full attention they need that day to have the best chance for learning. They cannot have someone in the classroom that is distracted and fretting over the next teaching assignment. Based on your last years schedule, you should be very busy in a very short time. Please considered only accepting teaching positions that you feel highly qualified to teach. With the selections available in your large district, that should not be a overwhelming problem.