I heard from the office staff that the UPS driver who is responsible for that area is not very cooperative.
Many of these drivers are actually independent contractors. So if the business uses a particular company (ie FedEx in their case), the driver knows the business well and will make the delivery at the right time, or even if the business is closed for whatever reason, the driver will come back later. The driver treats the business as his client.
We all learned from this experience and will post on the website that we preferred delivery by FedEx. We never had problem with UPS when NuForce was in Milpitas, California, but that was then.