How do I activate the 12-hour automatic shut-off feature, and can I turn it off?

The 12-hour shut-off is a default feature that automatically turns off the oven after 12 hours during baking or after 3 hours during broiling. To turn it off, press the BAKE and BROIL HI/LO pads simultaneously for 3 seconds until SF appears, press DELAY START until the display shows 'no shdn,' then press START to activate. (Page 6)