There are quite a few states with a one party law. In other words, as long as one of the parties knows that it is being recorded, it is legal.
Problem here is that UPS has a policy against recording on, or in, company property. And we all know that there are two sets of rules. One for us and one for them.
So it is highly likely that management does not abide by this policy, or feels that this policy does not apply to management, and records conversations without the affected employees knowing about it. This is legal in one party states.
If you, as an employee, record on, or in, company property, you will be terminated.
I have to say, though, that I am not aware, and have never been involved in a hearing, where UPS has recorded a conversation without the employees knowledge.