1. Don't ever give the office, your sup or manager your cell number.
2. If they say to call a customer, driver, or office, use the DIAD to tell them how many miles you will have to drive/time it will cost to find a customer phone. Even if you have a truck break down do not fall for the "we need your number for the tow truck driver"; they can relay messages through the DIAD. Let them know on no uncertain terms your phone and minutes are yours, and they do not have permission to call your cell ever. If they have your number now, tell them they are not allowed to call it or give it out. Block their numbers. Make sure you check the list in the office and scribble over it yourself if need be. File a grievance if they violate.
3. Use your phone if and when you feel like it. Never when they say to. Always dial *67 before dialing any UPS employee or customer.
If you do this consistently they will stop the nonsense, and will not ask you to call in/call so and so anymore. It saves time and hassle. You don't need to enable the sup or OMS who is to lazy to use the DIAD to communicate. You will be the last person they will want to contact to take stops off the lazy driver close to you.