8.a. is the key. DON'T answer your phone or acknowledge in the computer. It will go away (to the next eligible) if not acknowledged. Not officially a proffer but you don't have to do it unless it's acknowledged. I had a CP tell me just don't answer the phone if it's not a same day trip.
NEVER answer the call. Even on short call you should screen the call and respond within 15 minutes if necessary.