Unfortunately, there is no power off sequence option. You could create an activity with only the AVR device and name it "Intermediate Off" for example. You would hit this activity before hitting the "Off" button.
Note 1: The "Off" button is a built-in activity. It's like an activity without any device.
Note 2: You may want to use the Generic Activity (custom Activity) type under "Utility" sub-type to create your "Intermediate Off" activity.