Lets say both airports issue their first ATIS of the day, ATIS Alpha at 0700, but the weather or runway condition or navaids change at airport 1 30 minutes after ATIS Alpha. They would issue ATIS Bravo to reflect the changed condition at 0730. They would issue ATIS Charlie at 0800 to reflect the latest observation taken at that time. METARs happen once an hour usually unless weather is changing rapidly.
Meanwhile over at Airport 2 nothing changed until the next hour. Another weather observation would be made and ATIS Bravo would be issued at 0800.
The phonetic just confirms to the controller you have the latest ATIS at that airport.