The full error log is really extensive, let me know if you need the full thing.
Error:
Service unavailable (503).
Response status code does not indicate success: 503 (Service Unavailable).
CalendarApp.ProviderBase.Exceptions.AccountRequestException: Service unavailable (503).
Response status code does not indicate success: 503 (Service Unavailable). ---> CalendarApp.Common.Net.HttpException: Service unavailable (503).
Response status code does not indicate success: 503 (Service Unavailable). ---> System.Exception: Service unavailable (503).