The PCR is to allow multiple communication credits to be provisioned and paid for separately under the same Office 365 phone system tenant. The business case for this is that decentralized organizations like universities or global companies with separate decision making and cost centers in each location need to have the long-distance and toll free numbers associated with each department / site paid for separately by those departments or locations. Central IT, for instance, doesn't want to pay for the LD charges of the math, science, and art department, for instance. They also don't want to have to parse through a bunch of Excel reports to bill back each department internally. Our current customer with this request has 37,000 potential subscribers to phone system. This could be a showstopper for them.

I assume the request for billing address is to communicate paper mails where digital communication is not possible due to either geographic or physical constraints.

The service address would be know the most used location/geographically fenced location for offering a service as those services cannot be offered reliably beyond the confines of a fenced location like emergency services or signal quality services.

Third party hardware authenticators with gps or non gps geolocation/timing could enforce such a logic to support the service.

Take the case of a homeless traveller with a PO Box and without a place to call home will not be able to avail the use free/open services like Skype.