Discovered that the phone number in my contacts did not include the country code (all issues were with US and Canada numbers which have +1 for the code). When I added the country code into the contacts, the 'Maybe:' item went away and everything was back to normal.
Suspecting that this started happening as the system was looking for contact information in all my apps in addition to contacts. Some of the apps were showing with the country code included which might have confused things (ie. contacts without codes while others included the codes).
Simple fix on my side but would be nice is the system could understand based on country it believes it is in that a number with or without the (in this case +1) country code was the same. Note that calling on the iPhone in Canada it will work correctly whether the country code is included or not.