Originally Posted by Left Handed

Technically, you can be forced to IF they call you on your primary phone number (any one you choose) and you actually pick up but no other way. So just don't answer the phone and call them back. They can't junior man you if you call them. Or on acars, or meeting you personally at the jet, or when you call ops in range, etc. only if you answer the phone. That's why we consider it voluntary.