Unfortunately Smart Home Monitor in the Classic app does not implement exit and entry delays. My SHM Delay app supports these two delays, however you must learn to use the IDE to install apps and perhaps device handlers. The SHM Delay app has extensive documentation that will guide you through the process. Should you need assistance post a question on the forum.
This app, SHM Delay TrueExit, is designed to work in conjunction with SHM Delay, creating a real exit (alarm is off) delay versus a simulated (alarm is on but not reacting) delay.