I am curious if that issue is unique to the one person/family or if it is for all numbers, something similar happened for someone I helped on to PM. They picked a new number from the list since their old number belonged to their apartment (phone included in rent). When they tried to call a local number (mine and then a friend of theirs), it was acting like it was long distance and needing the 1 and area code. So best guess the number in the PM pool, despite being the correct area code, was probably from another city in the same area code region. Unfortunately ended up leaving PM to fix the issue rather than waiting to change the phone number to try again. On the flip side, mine was a PM pool number and worked fine (other than previously belonging to someone with a lot of outstanding loans so I was getting a lot of collections calls).
A similar issue happened when a coworker moved from one city in the region to another. Their address book needed updated with the area code otherwise the call would fail. If they didn't put the 1 before it, they would get the long-distance warning message (but never billed extra of course).
